Yeah the issue really lies in how Microsoft decided to go about backwards compatibility. Gone are the Ps2 days where you could just pop in a Ps1 disc and it would still work. Even the Xbox 360 wasn't backwards compatible with every original Xbox game. NCAA Football 06 for example is the only Xbox NCAA game that works on the 360. They build their architecture without backwards compatibility in mind and then see the demand for it and work it in, only now they have to make a dime off of everything they do.
Sony's even worse. You can forget about putting Ps3 or Ps2 discs in your Ps4 period. You either have to buy a remake, remaster, or use Ps Now.
Hold onto your Ps3s and Xbox 360s. Hell, buy a backup system if you can. I have the old 360 model, and I worry every day that it will red ring. I'll eventually get around to getting a slim model.
Our best bet at this point is to hope that Ps3 and 360 emulators develop nicely in the next 10 years. Preserving old games is becoming a thing of the past for these companies, unfortunately.