Well, depends on the player I think. The star of my chess club - has about 1983 ELO - uses it a lot. (He also told me Kramnik influences his play style a lot.) He introduced me to the opening and I simply didn't know it at the time. It can work at least as a surprise weapon. Furthermore, wasn't the Catalan actually created to be a way to play AGAINST QGD? It all depends on who who plays. I could tell you to ask him, but I don't know what username he has on Lichess. (All I know is his Lichess rating is over 2100.)
The QGD has been significantly more popular at the Super-GM level in recent years, so I guess that answers the question, from one way of looking at it.
Obviously, both are playable openings, and they both offer Black solid chances of equalizing the game. Anybody who dismisses either one of them knows nothing of what he is talking about.
Semi-Slav and Slav are great
My vote is for the QGA. When my opponent offers me a pawn, I take it... and try to hold on to it. It makes for more exciting games!
You can't post in the forums yet. Play some games!