Hi,
I think that chess.com's engine will create the same evaluation report regardless of the players' ratings. It would be impractical for them to design an engine that behaves differently depending on player ratings. From what I've seen, "Brilliant" moves are the ones that are not only the best move, but it was also only found by the engine after a deeper search. For example, if the engine evaluates a move like "Rc7" to be the best when it's at depth 8, depth 12, depth 16 etc, then it probably was an 'obvious' move and wouldn't be classified as brilliant. However, if you made a move that the engine didn't see until it reached a large depth, then that move would probably be classified as "Brilliant"
Since I started playing chess untill now, I have only got one "Brilliant" move and I am pretty sure that was by accident because at that time I was around 1200. According to chess.com definition, you get "Brilliant" when you find the "best" and "tricky" move. So, my question is, is there a certain rating that you must at least be at to get/make a "Brilliant" move? And if there is, what would the rating be?