Made an account just to chip in, I just got the exact same soft lock glitch. Picked up a qs bullet/molotov cocktail from the enemy closer to the balcony on the upper floor of the Derelict Building that's supposed to ambush you from behind the boxes. Exact same situation, can rotate camera and game is obviously still running but I can't get past the item pick up menu. Guess I won't pick up drops from that area any more? Hope someone figures out why this happens.
Viewing post in Bug that forced me to close the game, losing progress
Other pickups seem fine, just don't pick anything up from that one enemy! Most of the time its loot falls through the floor anyway, maybe it does all the time and pickups are grabs done in time (which as I speculated could play some part in this but I dunno). The wheelchair enemy who has a 100% droprate of 4 quicksilver bullets for instance is a-OK to loot from. And the two trolls down the lighted carpetway also are good to pick up their vial drops from. Just ambush sword guy... kill and move on.