Switch can play every 4K Scorpio/PS4 Pro game above 720p. Basic maths.

[SvennoJ]

Just wanted to point out that 4K is exactly 9x 720p. 1280x3=3840, 720x3=2160.
Hence the hidden beauty of a 4K screen as it can both perfectly scale 720p and 1080p content.
And thus switch will render games at 900p just to piss me off :)