The problem is what counts as a jerk.
Really? Because I think that's pretty obvious to the vast majority of people: Coercive, Abusive, Exploitative.
Coercive players are forcing others to do what the coercive player wants, against the other players' wills. This is where you see things like "oh lighten up, it's just a joke" or "c'mon, it'd be fun!" when it would only be fun
for that person.
Abusive players are hurtful to others, or knowingly and intentionally breaking the spirit of the game. The former is personal abuse, and generally quite obvious. The latter may or may not be obvious at first, but it becomes pretty obvious with time. E.g. the player who immediately rolls to attack whenever they "get bored."
Exploitative players take valid or existing elements (rules, principles, gentleperson's agreements, etc.) and twist them into grotesque shapes purely because they can. As an example, I don't use permanent
and irrevocable
and random death in my games. I had someone on this forum (semi-facetiously) say that he would treat that as an invitation to constantly do suicidal things, because his character wouldn't be able to die. That's clearly exploiting GM goodwill ("I won't take your character away due to Random BS", more or less) in order to get a ridiculous advantage.
And yeah I've seen people try and veto whatever and weaponize it. You also hear about it online I'm not to worried about that.
Okay. Such things are
exceedingly, overwhelmingly rare. As in, you're literally the only person I've ever heard of who has actually had to deal with that.
The weaponization is
almost never a problem. Genuinely. You have encountered one of the 0.1% of problems, while there's a HUGE HUGE HUGE HUGE swathe of problems where a DM sprang something deeply unpleasant or even traumatizing on a player.
Using food allegory if I'm feeding a crowd I wouldn't serve up seafood or vegan across the board. I would include those options.
Generally I'll book somewhere with a large menu.
Sure. That's the ideal. The ideal is not always possible. Sometimes, you have to make one dish that has to please everyone. It is simply being considerate to ask new guests if they have any dietary restrictions when you invite them to your house. It is rude to the point of
active malice to say, "We ARE eating peanut shrimp and steaks, I don't care if you're allergic or vegan or Jewish or Muslim, you'll eat it or you'll go hungry." Of course, in many cases, what
actually happens is not that, but rather that the DM thought to surprise their players with something exciting and perhaps a little provocative, but instead accidentally
traumatized one or more players, much as serving a delicious peanut-shrimp curry would be a pretty raw deal for a Jewish/Muslim/Vegan guest and genuinely inedible for someone allergic to peanuts or shellfish. Hence, having the tool of
asking for dietary restrictions when deciding what homecooked meal to make for new guests you've never entertained before.
It's all about being respectful to one another, and leveraging that respect productively so everyone--GM and player alike--can move forward comfortably and confidently, knowing that the way is clear. The X-card (and its counterpart, the O-card) allow GMs to push envelopes without risk of upsetting players. Lines and veils empower GMs to focus on things they know will be well-received even if they're dark or scary or gross or whatever, while avoiding the things that would
unequivocally always be a fun-ruiner for one person (and, thus, often a fun-ruiner for the whole table.)
You act like this is nearly always used as a cudgel to beat people with. It isn't. 99.9% of the time, it is used with care and only leads to
more respect,
more friendliness,
more mutual support. That's what all of this is for: to help people communicate with one another about stuff that can be really really hard to talk about, because nobody wants to be a party pooper but simultaneously nobody wants to be subjected to trauma while trying to enjoy a fun pretend elfgame with friends.