Those companies are known to be privacy hostile companies. Mozilla/Firefox, not. In fact, Mozilla claims the reverse!
For them to abandon privacy, is a betrayal, it's backstabbing behaviour. Feeling betrayed and wanting nothing to do with said software, as a result, seems normal to me.
Or in slightly different terms: If I wasn't using Chrome because of privacy issues, then Firefox losing the privacy advantage means they just ditched the only reason I was still using their product.
If Mozilla is abandoning their pro-privacy stance, they still have at least one thing (in my opinion) going for them over Chrome: Manifest V2 extensions. For now, at least.
For them to abandon privacy, is a betrayal, it's backstabbing behaviour. Feeling betrayed and wanting nothing to do with said software, as a result, seems normal to me.