20... rxd3 black lose with 21. qxr
Pseudoblunder Tactic - Rook Sacrifice

yes, as I wrote, white preferred to keep his queen on the kingside, and didn't like to trade queen (why trade queens when I can get that with the bishop?)
Also, you have to consider it was a blitz.
The main mistake was not putting rook in g1 or rook in a3 before moving the queen away from the 3rd rank
In a blitz I faced this position:
I wished to crush the white pieces structure next to the white king and bring my queen into action. So, I decided to lose my rook (further comments in the diagram):