Lanefan
Victoria Rules
Truth be told, in this particular example it is - because you included the words "trying to".Advocating for your character is not the same as trying to run like the Flash and create a tornado.
In advocating for one's character a player is free to try anything. The rules might stop what's tried from succeeding, as might common sense, genre conventions, or any number of other things. But the player's free to try it nonetheless.

Game's still hers. That said, it'd be a rather foolish DM who misjudged her potential player base so badly as to design a setting and-or system that appealed to exactly none of them, and thus the odds of this happening are fairly close to zero.So, it is hers, because she has put in all the effort to make it happen... and when she sits down with no players the game doesn't happen.
Yet I could do this - propose a game that would get exactly no uptake from a player group - tomorrow if I wanted. All I'd need to do would be to say I'm using 4e D&D as the rules system and they'd most likely run away as fast as their little feet could carry 'em. Therefore, I'm not going to be so foolish as to make such a pitch (and note this is hypothetical in any case: I can't see myself ever wanting to run or play 4e).
Ideally the players are driving the action. The game as a whole, however, remains mine.And during the game, the players are driving the action, but the game in no way whatsoever belongs to them, even though it would be impossible without them and they are shaping the directions it goes in?
That doesn't make sense.
As with the example with the Queen vs the Canadian Parliament and her never-used authority to overrule it, I hold an authority over the game I'll likely never use: that being to simply shut it down. No player can do this.
The character, however, still has to fit within the setting.So, you have already determined the only possible places a paladin could be made, and the possible cultures they could come from.
Usually decisions like that are the player's to make. Since the player is in control of their character
Clerics and Paladins have to follow a deity. I have a long list of deities (about 70 at last count) already in place, along with noting that there's further deities of very foreign cultures that remain yet unknown in these parts. I have three types of Clerics - War, Normal, and Nature - and Paladins; each deity supports some or all of these.
Some cultures simply don't support traditional* Paladins. The wild Celt equivalents, for example, just don't generally do heavy armour, mounted combat, or Lawful pretty-much-anything; meaning that while a Paladin of Celtic origin could be done as a PC it certainly got its training (and said its vows) to a non-Celtic deity. Other cultures might not support some other classes, and while these are noted in the game-world write-ups there's usually ways to work around stuff if someone is really hell-bent on doing something that doesn't make sense for the culture.
* - I say traditional because I've expanded Paladin alignment possibilities from just LG to also include CG, LE and CE. They're still usually extremists, though.

Yes, if it's something bone-simple such as what dice to roll when. If it's anything more complicated I usually defer to the DM.What part of that prevents a reasonable discussion and clarification of the rules, perhaps by another player who is highly knowledgeable in the rules? Why must the DM be the one to sort of rules confusion?
Here's a question, I know you are a fairly old player, probably considered a veteran. Have you ever sat at a table with a new player, and helped correct them when they make a rules mistake?
Mine does, along with lots of other character types.Would hard data like pointing to Oofta's post where he literally says he doesn't tolerate murderhobos help prove that a lot of tables don't tolerate murderhobos?
I mean, that would make three of us. You, me, and Oofta.
Or maybe, instead of me providing hard data, you could provide hard data showing that the majority of games do include murderhobos.
Once one has done any amount of DMing, one's view toward the game as a whole changes. It's inescapable.If a player happens to be a DM, they tend to care about the game as whole.
But those not blessed with the DM mantle tend to only look out for themselves.
Again, your bias towards seeing DMs are somehow special is... really blatant.