You're rather proving my point.
Explaining and "democracy" have nothing to do with each other. It's problematic that people think that they do.
The major problem, for me, as an extremely experienced DM and player, is that, through the whole time I've played all sorts of RPGs, a lot of DMs have banned things or created elaborate house rules, but many have not actually done so for rational reasons. Sometimes it's just as simple as a gut/instinctual dislike or something, or simple ignorance of the actual rules leading to pointless house rules. Sometimes they have some whole elaborate set of restrictions or house rules, but they don't have a rational basis (and no, some dubious "rationalization" doesn't make them rational), and typically don't make any damn sense, and sometimes outright break the game. In my experience, the people who do this typically can't/won't explain it, no matter how politely and kindly you try to get them to. Once I was getting someone to explain some elaborate house rules in the 1990s and the person realized how dumb they were without me even saying anything - in the process of actually explaining them he saw the contradictions and idiocy they embodied.
But sometimes there's some elaborate pile of house rules, or bizarre restriction, and it is totally rationally justifiable. It does have some kind of cool idea underneath it, and it does work. And those people never seem to have the slightest difficulty in, nor fear of, explaining stuff.
This is why it's important that DMs be willing and able to explain rules-changes they make. Not just so the players, who may themselves have very good reasons for wanting to understand, but so they can show that the changes actually have a rational/sane basis.
No-one is saying you have to give your players a 2-hour lecture before the first session, on the reasoning behind your house rules and restrictions, but if you're unwilling to or incapable of explaining them, that is a definite red flag, and it should be to you too.
I've seen this happen, but when you just say "We can discuss the ruling afterwards, if you like!", for me that has caused them to stop whining in 100% of cases, and in about 80% of cases, they then didn't actually want to discuss the rule, they were just okay with it, the main thing was that they wanted an opportunity to discuss it, a recognition that it was worthy of discussing, even if they decided not to take it.