Always surprised when some of these sites shut down. The operating cost seems low and putting on a few ads (ethical, non-intrusive, etc.) can net you passive $100+/mo.
It's more than money, they still require care and feeding. At some age (and I'm getting to that), you just tire of being a sysadm, esp. for "home"/hobby stuff.
This is why I'm scaling down my home infrastructure to SBCs and run everything on Debian with stock package repositories. It reduces tons of burden to something very manageable.