Agreed. It has long been the case that infrastructure critical to the
operation of the various wikis has been left without a clear
maintainer, or has been maintained only in the volunteer time of a
single staffer already fulfilling a full-time role. Teams would be
dissolved or reassigned to completely different projects after
completion, without the ability and/or willingness to even review
patches. That assumes that the team doing the work wasn't made up of
contractors who departed the Foundation when the project was
"completed", taking their knowledge of it with them.
This was a major factor in causing the technical debt problem, and
must be addressed to have any chance of solving it.
At some point we will have to admit that we have created a feature set many times larger than we have the capacity to actively maintain and improve. Either we make software development cheaper somehow (move the WMF to Romania or something), or we cut some of the non-software spending (but we already spend 50%+ of movement funds on software, and we'd have to increase capacity way more than by a factor of two to maintain all our code), or we undeploy most current features, or we'll have to put up with most things being unmaintained, which is the status quo. That's not to say we can't be smarter about it (e.g. microservices are a great way to have maintenance overhead spin even more out of control) or that maintenance efforts couldn't be better prioritized (e.g. the lack of maintainership of our authentication stack is somewhat wild), but fundamentally changing the current mode of operation (where most things are deployed and then abandoned to work on the next thing) is a pipe dream IMO.