Quite frankly, Sony doesn't go all in on their "legacy" but they have no need to invest there. For Nintendo, releasing the classics and having Virtual Console is a way to get old fans and new fans aware of their IPs while making a few more dollars on the side. Nintendo iterates on their IPs like no one else in this industry, so it's important that everyone knows who Mario, Kirby, Pikachu, Link, Samus, etc. are - because there's a new version of their games around the corner all the time.
Microsoft invests in their legacy as a market differentiator from Sony. They had the architecture from the 360 that lends itself better to playing those games on the X than Sony did between the PS3/4. So.... they tap that advantage and their own data already shown in this thread shows us that people barely use their Xboxs for that.
So what does Sony have to do to show they care about their legacy? Remasters have been discredited already in this thread. They've tried to bring PS3 emulation the best way that their hardware allows and that's via streaming which isn't a good solution. We know that, they know that. The market for PS1/PS2 isn't quite their to justify going into development to figure out how to offer those solutions coupled with the pain in the ass licensing agreements they have to strike up with various parties. It's just not worth it.
So then OP uses their failed Smash clone to show they don't care. I get that the funding quite wasn't what it should be, but neither was Smash 64's funding. The difference was in execution and timing. Sony TRIED, it failed. They're also not going to go balls to the wall and invest in a Smash clone when they're not convinced that fans even want that. I'm not convinced I even want that and I love Sony IPs and Smash.
edit - I will say, don't be surprised when the PS5 comes swinging out the gate with PS4 BC. Sony has been limited by their architectural decisions in the past. That wont be an issue going into the PS5 thanks to how the PS4 is architected and how we all guess the PS5 will be.