I disagree with most of this review. Yes a lot of the add-ons are not working anymore, but to be fair a lot of them were only ever useful for the desktop anyway.
I have been a Firefox user on android pretty much since it first came out and fenix is the best firefox on android by quite a margin and IMO the best browser on mobile. It's much faster than previous versions and subjectively faster than chrome. The major privacy and adblock extensions already are ported and the ui overhaul is a much needed improvement in particular the bottom bar and tab management.