In my club`s "non gambit" events, we will allow the Queen`s Gambit (Declined or Accepted) since it is not a "true" gambit. Also, a player has to get advance permission from the tournament committee to be allowed to play it. We, of course, grant it. To be honest, less than half the club plays in such contests but, to be fair, we run regular events simultaneously as well. For those who think that this is wrong, it is no more so than a thematic tournament in which all participants must play a certain opening/defense.
Very sensible approach.
For those who are terrified of gambits. Learn how to play one, and you'll like it. Don't pound on fun openings because you aren't good enough to play it, or beat it
1265 rated player tells 1600+ rated player that he's not good enough to play his feeble gambits. ROFLMAO.
Just because you're not good enough to play and/or beat gambits, doesn't mean you should attack them.
Did I ever say that? I said draws are boring, and wins are better.