Absolutely. I'm in 1815 and for the whole campaign I've been finding uberdeveloped provinces all over. Almost every African nation had at least a 30+ Sometimes more by 1600, lots of them in Eastern Europe and central Asia, all of Korea was 25+ by 1700, and I found a 42 development one between Siberia and Kamchatka of all places, in one of the most remote provinces in the game.
Debt-wise, I just sent a gift to Castille for 5300 ducats to cover their debt and lo and behold they actually used the money to repay the loans. Still won't help crush the Ottomans bc they got tangled in another stupid war, but that's a different story.
I think the AI weights development the most out of all its decisions but still manages (somehow) to have massive deved provinces with current tech . It is a mystery to me how they do it, however. The only powers I haven't seen developing provinces was the ottomans and mamluks.