Acadia is about all there is in the northeast, in terms of National Parks.
The positive side is that there's a ton of wilderness in the northeast that doesn't suffer from the National Park marketing badge (and thus any draw from the rest of the country), and so are less insane. Even so, some of the state parks within a reasonable trip of NYC (notably Harriman/Bear Mountain) can get a bit crazy.
The issue for locals wasn't so much crowding as I recall but concerns about restrictions to traditional sporting uses of the land. I haven't really followed how all that played out.
I've paddled through the "waters" bit a few times (geez, 20 years ago); lack of access would definitely help the overcrowding.
I haven't been up there yet. Soon. But like a lot of Maine lands in that general area, it's probably more paddling/fishing oriented than hiking (at least if you're into summits). (Even a lot of Baxter other than Katahdin is like that.)
In the Northeast you do see some spots getting a little crowded but it's absolutely nothing like the tourism-industrial complex that are the big western national parks. Acadia is about as bad as it gets here, but mostly it looks like "theres a lot of folks here." Yellowstone is a mess of badly driven RVs, yahoos ripping around on rented side-by-sides, just a lot of really ugly concentrated MURCA.