I used to have this with homeassistant and zwavejs. Every time I'd pull a new homeassistant, the zwave integration would fail, because it required a newer version of zwavejs. Taught me to build the chain of services into one docker-compose, so they'd all update together. That's become one of the rationales for me to use docker: got a chain of dependent processes? wrap them in a docker so you're working with (probably) the same dependencies as the devs.

My other rationale is just portability, and docker is just one of many solutions there. In my little home environment, where servers are either retired desktops or gee-that-seems-cool SBCs, it's nice to be able to easily move stuff independent of architecture or OS.

I guessed it was a "once bitten twice shy" kind of thing. This is all a hobby to me so the cost-benefit, I think, is vastly different, nothing on my setup is critical. Keeping all those records and up to date on what version everything is on, and when updates are available and what those updates do and... sound like a whole lot of effort when currently my efforts can be better spent in other areas.

In my arrogance I just installed Watchtower, and accepted it can all come crashing down. When that happens I'll probably realise it's not so much effort after all.

That said I'm currently learning, so if something is going to be breaking my stuff, it's probably going to be me and not an update. Not to discredit your comment, it was informative and useful.