The first photo might look slightly more dramatic than it is, here area two more:
So I tried to remove the gas compression spring of my new office chair from the sockets to send it back. It’s firmly stuck in both ends, and I read the recommendation to knock it with a rubber hammer. I couldn’t find one, so I covered the gas spring with some soft cloths and tried a regular hammer - and was a bit too enthusiastic. Is this spring still safe to use? I’m guessing/hoping that that’s not really the outer wall of the gas cartridge? It is still working, extends and compresses smoothly.
For many of these friction fit adjustable height chair and stool pedestals, I’d skip the rubber mallet and definitely skip hammers.
The easiest method is to place the flattest end between your feet and apply steady pulling pressure while gently rocking back and forth.