A bit of both, but columns on top tend to go so far to the right where they are not visible anymore.
Viewing post in Tables will cut off if they are too wide
Correct, i usually just copy paste them in. The formatting seems to be fine. But I would need to test how it would look with tables that go too big.
Realistically, i doubt one would be able to paste a giant table in a pdf. But a shrinked version of a medium table could work? No idea if implementable.