I used Firefox on Android on my tablet and it was perfect for my needs. Since the change, I went from using it every day to never using it. The reviews on the play store are brutal now.
The problem with Mozilla is that there aren't giving users what they want: Empowerment. Instead Mozilla wants the empowerment for themselves and to heck with giving users any control over the experience.
After the switch the reviews were extremely negative. Now looking at recent reviews it's like 50/50. There are still some people complaining about the new UI but you're not going to keep doing that months later. Those people are just gone.
The rating is increasing so the positive ratio is far higher than 50/50. There was an extremely vocal minority who left lots of negative reviews after the switch, and yes many of them may now be gone. But clearly new users are happy with it.
The problem with Mozilla is that there aren't giving users what they want: Empowerment. Instead Mozilla wants the empowerment for themselves and to heck with giving users any control over the experience.