If a bottom bracket threads in fine, a crank mates together easily, and the arms spin easily once everything is tightened...seems good enough for me.

The frame I built in a class was faced and chased because it needed to be after it was painted. Head tube was faced as well.
An old road frame from the 80s thst I did some brazing on had to be faced- the crank was tough to install and didn't turn easily.

I've sanded off powder coating on a couple bikes before, but every other frame I've built up thru the years, dozens plural, has been fine to just install and spin to confirm it's good.
Low standards, perhaps.