Im not an expert by any means, but that looks like a position that is far more likely to produce human errors than the "better" approach offered by the engine. Since it kept your advantage, I'd say that was a perfectly justified thing to do.
It is a crisp attack, but it is obvious that 21...Kg8 and 23...Kh7 is not the right defence: double loss of tempo and at g8 the king steps in the line of fire of the rook. He should have embraced 21...Qf5 right away, like he realised one move later.
You should have prepared the attack with 19 Kb1. The apparent loss of time Kb1 is nearly always a good idea after o-o-o, so as to protect the king from tactical counter threats like in this case Bxg5+ or Qxg5+.