Microsoft says Minecraft: Switch Edition's 720p resolution stems from issue with docking/undocking

Coming from TIME magazine...

Microsoft notes that Minecraft‘s 720p docked/undocked resolution isn’t a question of system power, but stems from issues currently experienced shifting from one resolution to the other when docking/undocking. It’s possible, albeit not confirmed, that Minecraft for Switch could hit 1080p docked down the road.

Looks like there's a kink or two to try and work out, and that could result in the resolution in docked mode getting bumped up a bit. It's not a guarantee, but at least Microsoft was forthcoming about the matter.