My problems with cloud based Emulation a.k.a PS Now for example:
1) My Internet is garbage and too slow to utilize PS Now.
2) I don't want to pay extra for more subscriptions on top of PS+.
3) I prefer emulating it off my hardware rather than rely on Cloud Servers far away from my home.
4) I can't play my physical copies of games. XB1 does kinda support that but it only has selective list of games available so no old titles with any licensing.
5) Speaking of which, that means you won't be able to buy and play certain games like Gran Turismo, Tony Hawk, Smackdown Series..etc and on top of that, they are some games that will simply not be available for one reason or another (Developers Studios closed, games that are too niche, remakes available, Developers doesn't care and so on).
Remember when a few selection of PS2 games were sold on Playstation Stores, each for $15 or so, few years ago? Sony pretty much forgot about them because i haven't seen them adding any other titles nor the list for "PS2 Classics" exists on the main page anymore.