Did they not let the devs use any of the cool villains?
Without reading anything after this post. A lot of the times, yes. I've seen a number of developer interviews over the years where they talk about how awesome it is that they get to use some "underused" characters in their game. When it's really because they can't use stuff that might plausibly turn up in the movies or whatever.
I mean, there's obviously going to be a new Green Goblin in an upcoming Spider-Man film right? But if they put him in the game and design him and everything, that conflicts with whatever the movie comes up with if they're supposed to be set in the same universe. Everybody in the world can get over this, except the studios because there's internal politics power plays involved.
One of the benefits the PS1 era Spider-Man games had was they used the defunct animated series as a base so could use any and all of the villains and didn't have to worry about film approval, but Treyarch's next gen sequels that were supposed to be movie tie-ins couldn't use stuff not run past the studio first. Activision later separated those yearly Spider-Man games from the films so that they could use Venom and other popular villains in the game. (Along with distancing them from Spider-Man 3 and the films that came after, also the fact that they wanted to put them out every year or so.)
The Rocksteady Batman games started their own universe and went totally opposite Nolan's "realistic world" by embracing all the unrealistic characters and such, whereas the Batman Begins game was so hamstrung by following the film plot near exactly that it sat for long periods in development (as they waited on stuff they could use and getting access to stuff like the Tumbler) and then was rushed out to match the movies date. (As a kicker, the game used a lot of mechanics that Asylum later got praised for "introducing" like needing to use stealth, using the different gadgets, scaring enemies which makes them easier to take out, some gliding, etc. rather than being just a brawler like past Batman games but the game as a whole wasn't executed all that well outside of the presentation as it only had like a year and a half of development and was tied so hard to the movie plot that there's no real villains (bosses) to fight in it except random gang guys and Zsasz who they powered up from his cameo in the film. While Asylum got to use the whole rogue's gallery and more.)
Of course, this has also happened all over the place as these film franchises have taken off, Marvel has even been futzing with the comics of all things due to what licenses other companies still hold, namely the X-Men and mutants.
That reminds me, EA's Superman Returns ran into the same problem as their Batman Begins game. The film has no villains to use in a game. And they had to run everything through the studio. Whole chunks of the game disappeared from previews to release.
But damn is Supes breaking the sound barrier while flying in that game still hott. Even on the hideous PS2 version and less hideous Xbox version. Not to say that the 360 version isn't also kinda hideous for a 360 game.