That Firefox logo was simplified, but not oversimplified. Even with a very small icon size you can still tell it’s a fox that is (on?) fire. The Firefox Family logo is oversimplified, just being a swoosh, basically.
The new reddit logo is pretty awful but both Firefox logos are fine IMO. They are both pretty well done, just in different styles.
I used to not like the new Firefox logo when it first came out, but by now, I couldn’t do with the old one, it looks so much… And I bet if they changed it back, it would take me 2 months max to switch opinions right back.
At some point I have to accept, I’m just an ape of habit.
Honestly, its considered a hot-take but I do like minimalistic logos cause they are easier to recognize. Also they tend to better fit with the rest of the UI and products.