I say that because the public generally underestimate the cost of decently exploiting back catalogue in film (storage, masterisation and restoration), while overestimating its commercial appeal. Games are different obviously and I don't doubt MGS has some appeal but even with the new commercial opportunities to monetize old stuff, the media game is still first and foremost about new products. I know I already used this exemple a couple if times but Sega abruptly stopped making HD remakes for a while after the lackluster sales of JSRHD IIRC and even a surebet horse like RE is "only" moving 1m units at a budget price (very good, mind, but not the kind of crazy numbers now expected from tentpole releases).
A simple conversion to be sold on Steam would be mostly risk free I agree, I'm less positive about a full fledged HD remake to today's standards. Even if, I don't think Konami is willing to make any budget effort now anyway. So I guess we agree on that. They're not terribly in need of earning goodwill, despite the PR sugarcoating.