I doubt we’ll see broad 8K support in triple-A games for some time, but 2D games arguably benefit more from higher resolution, anyway. The Playstation 3, which ran most games at a maximum of 720p (many, like the Grand Theft Auto series, rendered internally at 640 or 512), actually supported 1080p output, something the Pixeljunk series used to great effect. I wouldn’t be surprised to see a sprite or vector-based game on the PS5 that does something similar with 8K.

The PS4 works fine as a 4K Blu-ray player though. Having the hardware to support 8k output means you have that covered when it becomes widespread

PS4 (even the Pro) cannot play 4K Blu-rays. I'll predict that the PS5 won't be powerful enough to handle 8K AV2 video or whatever ends up coming out.

PS4 Pro has the power to play 4k blu rays but doesn’t have the capability due to either the drive or licensing fee.

Power isn’t the issue as the Xbox One S is equivalent to a base PS4 and handles 4k discs fine.