I've written plenty elsewhere about review bombing ever since The Last Jedi was subjected to it, and I have plenty to say about it now.
Review bombing is invariably an act of protest, not an expression of legitimate criticism of the objective quality of a game, film, etc. Review bombers swarm aggregator sites to issue the lowest-possible score in order to tank the user review average of the work, ostensibly in the hopes that it will damage the commercial viability of the product or at least draw the attention of the publisher.
Sometimes it's done because of a publisher making business decisions that the audience doesn't approve of. In the case of video games that could be something like adding loot boxes to a game, putting obtrusive DRM in a game, or even something merely annoying and inconvenient, like a game not being ported to a fan's preferred platform. In some of these cases I can understand the outrage, because sometimes the games industry (esp. the big companies publishing AAA games) does some really shitty things that are frequently outright anti-consumer. I don't particularly agree with the practice of leaving a 1/10 review score because a game has some awful monetization scheme that detracts from the experience, and I think such scores should be reserved for games that has terrible, awful, broken gameplay or is otherwise is enough of an unplayable mess to warrant such a score (think E.T. or Big Rigs: Over the Road Racing). But I do understand it.
But then you get to reasons that are arguably not even valid. A lot of review-bombing is done for reasons of fandom. Sometimes it's because a large enough group of people don't like a particular series (Call of Duty always gets this treatment on Metacritic; usually decent reviews from critics and still good sales, but with awful Metascores for nearly a decade now). But usually it's because you get fans that are angry that the film/game/etc. did not meet their subjective desires as fans. But a character being portrayed in a way that isn't congruent with someone's idea of how they should be portrayed, or a secondary villain not getting sufficient background information before being offed, or quibbles over fictional technology does not make a film worthy of a 1/10 score. These are not legitimate criticisms of the screenplay, script, cinematography, acting, visuals, and other artistic aspects of the film.
And these days it seems to be increasingly the case that review bombing is political in nature. In today's internet culture wars, review aggregators sites have become a venue for bad-faith actors to attempt to sabotage works they don't like for political reasons. Most of this usually comes from right-wing "anti-SJW" types. While there are no doubt at least a few people who just don't like The Last Jedi or Captain Marvel or the new Watchmen series on a purely artistic basis or because those titles didn't meet their preferences as fans, there are far too many people out there giving lowest-possible scores and leaving commentary complaining about "SJW propaganda, "feminist agendas," "forced diversity," and the like. I think it's reasonable to conclude that people would be far more motivated to leave negative reviews for political reasons than for non-political reasons.
When people who go on RT or Metacritic or wherever to drop lowest-possible review scores because they feel that certain content in the film offends their political sensibilities or because they're just outraged fans angry at a film for no particular political reason, they aren't judging the film or show by the quality of its acting, screenplay, cinematography, etc. They aren't judging the game on the merits of its gameplay, story, etc. They are quite simply acting in bad faith. Such acts of protest are not legitimate constructive criticism of a creative work. It's someone pitching a temper tantrum because they're angry the world doesn't always conform with what they want out of it.
When I saw some of the outrage over The Last Jedi and Captain Marvel, my initial reaction was "This is not normal adult behavior." I simply fail to comprehend how anyone could ever feel this amount of white-hot loathing and resentment over a movie. A MOVIE! I simply cannot fathom why anyone would think it is okay to get that bent out of shape over a work of fiction. I have personally been called "ignorant" and "deluded" for liking TLJ and suggesting it to other people. I have seen people turn their dislike into crusades. I have seen people demand directors get fired. I have seen people conjure up conspiracy theories about Captain Marvel's box office performance (because the "woke" film did not "go broke," and in fact was a smash hit). And I've seen worse than all of that. Review bombing is far too often simply a symptom of the worst parts of toxic fandom.
In certain circumstances, it pays to be skeptical of audience review scores, especially when there's clear evidence of review bombing a popular and critically lauded work, and doubly so if there are significant amounts of people angry for political reasons. In those situations, the aggregate audience score is extremely unlikely to be an objective assessment of the actual artistic merits of the work in question, while the professional critics' score is more likely to give a better picture of how good the film is. Not liking a good film or game is normal. Not everything clicks with everyone. I know people who legitimately are put off by entire genres, like horror or sci-fi. While there is no accounting for taste, there is accounting for people acting in bad faith. Audiences liking movies that most critics thought were average to bad isn't anything unusual (and there's nothing wrong with treating a bad movie as just dumb fun; there's a reason "so bad it's good" is a concept that exists). But it's much rarer for movies that were loved by critics and popular with general audiences to get severely panned at places that allow user reviews, and in recent years it seems like it's increasingly due to political reasons and not the artistic merits of the work in question.
When a film like TLJ gets a 90+% average review score from professional critics (the people who actually do study and critique film seriously as an art form and thus are more likely to be objective than fans in regards to its artistic merits) and wins multiple awards but a bunch of disgruntled fans (and more than a few right-wingers) give it a bunch of 1/10 reviews to try to drag the average down, I think I'm going to side with the professionals. "Critical dissonance" does exist, but this is ridiculous. There is nothing objectively wrong with films like TLJ or Captain Marvel that puts them in league with legitimate all-time critical flops.
You know. The films that actually are cinematic atrocities.
While professional critics are still influenced by their own personal beliefs as well, they are far more likely to give honest criticism of a film, and many movies that express themes or values often deemed conservative have been reviewed well by critics because they were good movies, and plenty of movies with overt progressive themes have been given middling to poor reviews because they were bad movies. How often do we see that same kind of objectivity from angry fans or anti-SJW types? Very rarely if ever, that's how.
