This is a feature and not a bug.
Conflict is not a negative thing in and of itself. It is very helpful when handled responsibly.
Hashing out the kind of game everyone wants to play is exactly what you should do before committing to a campaign. If the table has reasonable adults then you can find a game that is acceptable to everyone.
If the table doesn't have reasonable adults, then it probably was headed for trouble anyway.
In practice, this means going back to that 'default' in every game because 'reasonable adults' usually adjust for the four to twenty other people who might be a part of their game, or regularly leaving playgroups/players to try and find one that doesn't take issue with the game you want to run, except that takes even longer because its emotional labor to figure out exactly where the differences lay and what will and won't be ok, and who is responsible for giving or leaving when you reach an impasse can be draining in and of itself.
Well, that or engaging in some exhausting gamesmanship to leverage the paucity of GMs into tolerance of a compromise in which you get some of what you want out of the negotiation, which seems to be the popular method.
This is all IN ADDITION, to the very important work of setting boundaries to make sure everyone is emotionally and psychological secure in the game thematically, scheduling, prepping actual game content, curating a homebrew collection, managing spotlight and personalities during the session, and so forth.
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Pretty much all of this, just kind of went away when we switched to Pathfinder 2e, because it provided a common framework that requires way less negotiation and litigation for everyone to be satisfied with. Its not the
presence of conflict that bothers me, its the amount-- we still quibble over what things should be what rarity, whether anathema is going to mean anything, and whether to use the baked in alignment system, what character personalities can mesh with the group. But, its pulling so much more of the weight for me by making these decisions in a curated way, giving my players the toys they want to use, giving me systems that I don't have to negotiate to add because they're already there, and not asking me to balance it all.