No reason.
It’s just that he’s been saying he can’t make the last 2 or 3 returns available because they are under audit. He has some returns that are complete and accepted, which show how he has customarily done business. If he wants to release them (and I mistakenly assumed he had), that’s his business.
All he really has to do is the more general broad range asset disclosures that politicians seem to do.
Is there a legal requirement to release tax returns?