My only problem with anonymous is you have no idea if the person on the other side is 1100 or 2200 ... I just use Zen mode in Lichess, I know the other person is about my level, but I don't care what the numbers area .....
Yup, that's good to point out. Zen mode helped me enormously when tackling puzzles, because just seeing how I had fared earlier was making me think about my performance instead of puzzles.