My TV is 4k. The Steam UI alone is still a laggy mess at 4K. Setting the Deck at 1080p makes the whole thing really blurry. While upscaling games from 720p or 1080p to 4k looks better. Until they changed something about the FSR settings and it now cripples the performance at 4k as soon as you turn it on.

A Steam Machine aiming for Xbox Series S type of performance would be sweet.