they mentioned they found the "remains" of fish, presumably liquefied along with possibly some bones

Depends on the conditions, see mummies for examples. Don't expect fresh looking food though, it probably amounts to super dry rock looking objects

Reminds me of this article[0] about a guy that revitalized 4500 years old Egyptian yeast and baked bread using old grains.

[0] https://www.smithsonianmag.com/smart-news/bread-was-made-usi...

The guy, Seamus Blackley, a game programmer who proposed the original Xbox, no less. Also made Trespasser (1998) realistic open world 3D game with physics engine [1]

[1]: https://www.youtube.com/watch?v=OSDa4VZbJzI

The article didn't imply that the food was still edible.

I wasn't implying that either. But how can you recognize organic food after 5k years? In my compost bin it lasts only a few weeks :)

Composting is a process specifically intended to break down organics. A closed tavern in the desert isn't likely to have the same conditions, and I'd imagine the remnants of the fish are largely bones and scales of the sort you wouldn't put in home compost.

You can't compost food in the desert, it's to dry.

bones, seeds etc. can fossilize

They can, but usually not on the relatively short timescales we use in archaeology. It's not what happened here, for example.

maybe they found it in a sumerian freezer

5000 year old fish would probably be excellent fish sauce by now

You've never found McDonalds of unknown age under the seat of your car?