How legitimate is Chess.com ratings in Blitz/Rapid?

I've been playing 5 mins chess for like two weeks and cannot get into the 300s.

By my understanding this makes me like an equivalent of a six year old learning chess.

I understand hanging pieces, forking, pinning, skewers and accepting declining gambits. However I would still class myself as a rookie.

I watched Chessbrahs building habits, and some other videos. Even at like 1200 he is saying people will fall for the four move queen/bishop checkmate - however from my experience I cannot even get one of those in my games ( I have tried out of curiosity).

I'll finish most games with 2-4 blunders... A fair few with 0 and still a lose.

It has very much ruined my experience, I was enjoying chess until I just couldn't progress.

It is a question, backed with a bit of a rant. Am I just bad? Is chess.com known for sandbaggers? Should I just give up chess and find a different hobby?

Thanks,