Are you sure that Firefox is a good alternative, given all the things they’ve been doing lately? And why not fork, by the way?
Also, Google is funding Mozilla, so… yeah.
Because it’s still better than Chrome? They still support ManifestV2 which is necessary for AdBlockers like uBlock to work properly
Every other browser uses chrome and just puts their stuff on top. So you either use actual Google chrome, a rebrand (I know it’s not exactly that nor that simple), or you use Firefox.