I think Uncle goes a bit too far and think Nintex, sigh, is closer to the probable storyline here. Nintendo could have sent out development kits with a 4K output as that's borderline trivial to support on a devkit, it's a port. And developers will not care how it runs in 4K, they just want it to output to their monitors.
But that's not what the Nintenyearolds are hearing and writing pages upon pages in that thread about. They're hearing Switch 4K. Except there's almost 100% no chance Nintendo is producing a Switch with the "secret sauce" to output
games at 4K. The current one can't even do 1080p legitimately even though that's "supported" and some games do it. (No, I don't care about five years in advancements in technology
elsewhere.) And they certainly aren't producing one that can do 4K
undocked because they're fucking Nintendo.