How is it mediocre? Is it because of the CVEs that have been released in the prior years? I recall GitLab also having quite a bad week of CVEs in February[1].
How is it a bad ecosystem? If this is about plugins in order to do things, I actually like this framework - it lets there be specific owners for portions of the open source development.
Self-implodes? This seems like it would be tracked as a bug. I've encountered an instance where Jenkins wouldn't start due to a crypto issue but that was due to a bug and all I needed to do was install a patch.
I think that using Jenkins can be a thought of a serious option if like anything else, you follow security protocols ie: don't allow public access, maintain RBAC standards, have a maintenance schedule.
[1]https://about.gitlab.com/releases/2022/02/25/critical-securi...