Do we know that for sure? B752 has 57t to work with (MTOW – OEW), of which ~19t goes to pax/luggage in a TATL configuration, leaving 38t. But the tanks only hold ~34t, so that appears to be the limiting factor. A321XLR MTOW is forecast at 101t. At 101t it would have 50t to work with, of which ~18t goes to pax/luggage, so ~32t of fuel. I'm unclear on the tank size of the XLR. The A321neo holds ~24t, and the new rear center tank can hold almost 10t; if they're additive then it could hold a full 32t.

At any fuel load of 29t or more, the XLR will surely give the 752 a run for its money in range. At near-equivalent fuel loads I can't see how it could possibly have less range. Yes, it will take longer to get to FL360 or above, but that's going to be more than compensated for by the GTF/LEAP engines that have considerably lower SFC and lower max thrust than the PW2040.