In short: I used an elytra to reach a bottom of a hole to retrieve an allay, but died due to fall damage at the bottom. Using a totem to retrieve my loot, there was nothing there but the allay. No items, no experience. I closed without saving and booted it up again. I started at the top of the pit with the totem, and this time grabbed a water bucket just in case the totem caused something funky. Upon reaching the bottom again, nothing but the allay.

 
In full: After digging down a 1x1 shaft, I had an allay follow me down, so I had to rocket up with my elytra instead of towering out. After waiting a minute for the allay, I realized it had unloaded and I would need to go back in and bring it up another way. I jumped in the pit, deploying my elytra and slowly glided down. The allay loaded back in, and just as I reached it at the very bottom, I died to fall damage. I guess I wasn't going slow enough when I thought I was. I may vaguely recall hearing and seeing my items drop, but I can't confirm if that's what happened.

Quickly, I grabbed a totem and ran back to the spot which was nearby and jumped in the pit. When I reached the bottom there was nothing to be found but the allay. There was no items or experience. I immediately closed the game without saving to see if that would somehow undo the last few moments. When I booted the world back up, I was at the top of the pit with the totem I had used still. Thinking and hoping there was an issue with the totem, I grabbed a water bucket and rode it down without dying or taking damage. Upon reaching the bottom this time, it was the same story. The allay was there, but no items or experience.

 
Other similar reports I've found are all listed as resolved, but I've made this post because I seem to having some issues despite them.