I've created this task on the topic of shared hosting:
https://phabricator.wikimedia.org/T113210 as a proposal for the upcoming
Wikimedia Developer Summit.
If anyone on this list is currently running mediawiki on a shared hosting
platform, I would really like to hear from you on that topic, either on the
list or on that phabricator task. So far all the discussions on that
subject I've seen seemed to be done "on behalf" of people relying on those
platforms, and I have yet to hear direct testimonies and opinions from
people who are running mediawiki that way.
The main questions I have for people in that situation are whether there
are blockers for them to move to more modern vm-based or container-based
hosting platforms, or if they prefer to stay on shared hosting for specific
reasons, etc. Basically, tell us why you're on shared hosting for your
mediawiki install(s).