The problem with HOAs is the people serving on them are often the people you wouldn't want to have the authority to veto things or to complain about things.
We had a complaint because a yard item was deemed to be "an eyesore", which necessarily inflamed and hurt the feelings of my wife. The notice of violation should have just stated, "you're not allowed any decorations on this part of the yard because it's common area." No reason to hurl a personal insult.
But as you stated HOAs do help prevent the one imbecile on the block that doesn't mow the lawn or who refuses to paint his house. They are also good about preventing huge RVs being parked out front or visibly.
I remember one notice I once received because there was a smudge of dirt on the garage that the HOA's worker placed on the garage door. So HOA people are necessary needle-nosed ding-dongs with nothing to do.