I second everything Uncle posted.
I was open to HD graphics, despite all the bugs that came along with them, if players preferred that. However ever since HD graphics started crashing the game, in I think patch 1.34-1.36, I just force disabled them. Since disabling HD graphics, I realized that the public lobbies of my maps fill up much faster. This might be a coincidence or - correct me if I'm wrong: if you have mixed (SD and HD allowed) then it restricts it to only Reforged owners, while only SD allows Frozen Throne and Reforged owners.
EDIT: Some recent culture in gaming puts heavy emphasis on graphics. I think that's coming from corporate developers though. Most players seem to be ok with moderate graphics as long as the game is fun. A good example of what I'm talking about is the whole Elden Ring drama where it seemed other developeres were horrified by supposedly substandard graphics while many players reviewed the game positively. WC3 is over 20 years old so I don't think a lot of players are coming here for cutting edge graphics. I'll stop here before I get into a angry Blizzard/Reforged-hate rant lol.