Same. Without uBlock Origin I'll drop Firefox. There are very few reasons to put up with its "niche browser that nobody tests" status if they won't even allow me to block ads. They should just give up and end Firefox development already if they're going down that route.
I'm doing as much to keep Firefox alive as anybody.
Wherever I've worked as a dev in a decade I've always developed Firefox-first and let the testers turn up Chrome issues. So the products that I am involved with just work with Firefox all the time.
I know there are a lot of people like me, people who are passionate and engaged with technology but have problems with "big tech" and if they turn people like me away than it really will be a "niche browser that nobody tests"