Most switch games look like shyt on my 4k TV so it gets used exclusively as a handheld. Only mario kart, odyssey, and smash bros seem to upscale decently when docked, every other game I've played look and runs noticeably worse on a TV.
I've said it before but it was a missed opportunity not having hardware built into the dock itself to help with performance.
And I highly doubt Nintendo will improve on this with the successor since they now they can sell like hotcakes with putting in low spec hardware.