It's been a hot minute since I last looked at the most recent list, but the short of it is that the WMF likes to release extensions onto Wikipedias that ship with a ton of technical bugs, aren't tested beforehand by the Wikipedia community for usability (which is ironic given the WMFs obsession with making tools as accessible as possible) and when the complaints get leveled, the response from the WMF basically ends up being "yeah so there's no budget for that". Rinse and repeat for a ton of tiny technical issues that affect all their extensions on the regular. It's a bit odd to be putting so many engineers and money onto lofty projects when the maintenance of Wikimedia extensions is in such an extremely precarious state already.

The most evergreen example of this is and probably always will be the rollout of VisualEditor, their WYSIWG editor. It was completely unwanted, was proven to be not ready for general use (due to all the problems that plague "combining a WYSIWG editor with a code view"), yet forcibly deployed on all Wikipedia languages without much room for warning or feedback. After that, the WMF promised communities the option to opt-out if they didn't want it... before violating it on the German Wikipedia because they voted to not roll it out. To my knowledge, VisualEditor hasn't improved over the years (beyond "rewrite Parsoid into PHP"), but editors have just gritted their teeth. That's the extreme example, but the WMFs relationship with building features for Wikipedia is... pretty much in a vacuum from what users want. A lot of their projects seem to be conceived by WMF managers first, without consultation to their existing community of volunteers.

Which is I guess fine for moonshot projects like Wikifunctions (since they don't involve the volunteers before release) but results in a lot of friction when a managers pet project is forcibly rolled out on all language Wikipedias. Very few of their big extension deployments have gone smoothly with the community. I distinctly remember the Minerva skin (mobile Wikipedia) needing tons of changes and improvements before it was usable as well, after it was already rolled out and caused a ton of negative fedback.