High switching cost compared to finding another extension (e.g. uBO Lite), even if the resulting experience is worse.
You’re not wrong about the high switching cost.
Switching from Chrome to Vivaldi (because of Chrome’s whole FLoC thing) to Brave (because I didn’t like Vivaldi’s layout) to Firefox (because of Brave’s whole thing) was a pain.
And I don’t mean as a whole. Taking the time each time to change from one browser to another was always a pain. Transferring bookmarks and passwords was easy (Chrome and Firefox are at least compatible in that regard), but transferring extension settings was a whole different beast.
Some extensions had cloud sync support. Others had local export support. Some didn’t have either kind, and I’d have to manually copy the settings from one browser over to the other. And that’s not even getting into finding replacements for the Chrome-exclusive extensions (of which there were only a few, thankfully).