Fort went from the best enabler of Pyg infinites in the game to the best enabler of Pyg scaling items in the game

In case it didn't quite click reading the patchnotes, a gold fort enables textiles silk and beast of burden to multicast, and a diamond fort enables regal blade, dog, and lion cane to multicast.

You can keep these scaling items around and instead of them falling off in the lategame, grab a fort to raise the cooldowns of your opponent's items and break up their synergistic endgame packages while effectively doubling the effectiveness of scaling items you've picked up and scaled up throughout the run.

There are lots of other lategame synergies with fort to find, too - particularly with the legendary weapons that are rare drops from monsters, but this is the most straightforward situation that fort gets value in.