I'm starting to get uncertain about how much longer there will even exist future Playstation hardware. Apple and Google phones have devoured the casual/mobile gaming market and as that market hits saturation they'll be eyeing the prestige AAA gaming market. It's not hard to imagine that a modern iPhone or flagship Android has the hardware chops to run something like GTA 6 at an acceptable level of quality. Continuing the GTA 6 example, it's not hard to imagine Rockstar taking one look at the TAM of current-gen console owners vs. the TAM of high-end phone owners and realizing how much more money they could be making by porting it to the majority platform. With the right games signed on (GTA, FIFA, Madden, COD), all it would take is either Apple or Google releasing a $100 dock-plus-controller to absolutely blow the traditional console makers out of the water; everyone either needs or already has a phone, and nobody needs a dedicated game console.

The point being, it's not much comfort to preservationists to consider the longevity of a proprietary platform that might realistically be defunct in a decade. I don't know if there will be a PS7, but I tend to doubt there will ever be a PS8.