Have you looked at Nvidia GeForce NOW? It's like $10/mo for a pretty decent streaming gaming rig. I'm very happy with it - I don't have to deal with Windows and can play AAA games on my Macbook Pro at 60Hz (1080p).
I think you just answered yourself. Some of us like to play games at 4K at 80Hz+, with no subscription fees, no internet bandwidth requirements, no added latency, and ability to mod.