i believe it is ALYURFED
Who has the highest Puzzle Rating on chess.com??
65535 = 2^16-1
I think this is an artifact of the data type that they use to store the rating. Of you start counting at 0 then this is the highest number you can represent with 16 bits.
This makes me think that the puzzles don't really get progressively more difficult in proportion to the score infinitely.
In my knowledge its
https://www.chess.com/member/peshkach
If there is anyone higher pls write over here