I think that remakes for video games are useful. A movie from the 1930s can be restored to be look perfect on a BluRay. Because there are old movie roles, you can use as a Master.
But you do not have this for a video game. Video games can look and play very dated. Video games can be getting much older than movies.
So yes, a remake is actually useful. You can get an older game and to make it feel like a complete new one. A remake is actually much more desireable than a remaster in an interactive media like video games. Because video games are simply played differently today than twenty years ago, also as i said, they simply look old and plays old, too. A movie is still a movie you can watch and the most problem of older movies are actually computer generated special effects, because they were created from the same limitations as video games. But otherwise, in Movies you do not have technical reasons to create a remake. Old movies can still look like new ones. Sure there are movies, where a remake would also be better, but mostly because the original is a bad movie due to a bad script.
But video games get bad, because they look old and does not offer gameplay mechanics current game in the genre has.
Age of Empire: DE is a good example for a game, where a remake would be much better than a Remaster... because in its core they kept the same game, but made the graphics better... this contrast is simply destroying the Zeitgeist this game has. Because it looks new, but it still has the old gameplay which does not feel right to such graphics. In comparsion to Starcraft 2, Grey Goo or Ashes of Singularity... ouch. And these are the titles a newly released RTS has to compete with. It is not 1998 anymore.
Yes, you are right, for the few people that still love a game from 20 years ago, they do not need a Remake or even Remaster. But it is a complete new game with an old story for a new generation of players. I do not see the problem in this. It would be much worse if they would release the same old game with a few new graphics only and make the impression, that they are simple ignoring all the developments the genre has in the last two decades.
If there were no SCP and FreeSpace 2 with the graphics of FSO 3.8 and MVP2014 would be released as an official remaster by Interplay, i actually would dislike this kind of release, because the gameplay is simply still the same from two decades ago with all the very confusing control options for new players (i do not know a person who need more than 1/4 of all the individual keys the game has to offer), lacking a good controller support (joysticks are nothing more than a gimmick today, that's just how it is) or that you have to create a good controller config for yourself, the extreme long loading times by today standards and some convenience options especially on the lower difficult settings. And even there were not much gameplay developments in this genre since the original, at least there were some and they should be considered and not be ignored. Some of these developments are even part of some SCP campaigns during the last couple of years.
So a remake is not for the people from back then, it is for the people from today.
And i think that some of you have children already? Would it not be good, that your child can comprehend your feelings you had as you experienced the story of FF7 for the first time? If you give show your child the PSX original it would maybe say "What? You played this ugly and unintuitive ****?" instead.