Yeah I know. It’s an old game but it’s still very much under active development. So not really “old”.
Well, yah, I don't really see anyone adding it to a dead game. But anything that's old and generating money that's still actively played is a good candidate. Rocket League I think is UE3. Perfect game for FSR. Sure, it runs very easily on pretty much anything if you turn down the settings. But FSR could allow some really low end PCs to play the game at high frame rate for competitive play without looking awful.