I've just started a new game and it looks like Aggresive expansion for provinces is much higher. I guess in fact it's the same, but shows higher because it's more real?
They tweaked the interface so that the number you see in the screen shows the
highest amount of AE gained, rather than the base. It's in the 1.19.1 patch notes, I believe.
This is dumb for numerous reasons, including the fact that It's normally going to be the highest on the nation you take the land from (due to culture), but they're completely irrelevant because you'll have a truce with them.
The numbers are still the same as in 1.18 (plus or minus margin of error); if you hover over the AE number listed you can see what each country (that goes over 50 AE from the peace deal) will incur against you. And you can still see the base amount of AE gained in the text description of the peace deal, on the right side of the peace treaty window, if you scroll down; this is another reason the interface change is stupid, since it was changed in one spot where it doesn't make sense and not changed in another spot where it would have.