Extreme logical fallacy. The 100% faulth is on the player. This is the equivilent of a parent buying their kid GTA5 even though the game either says 18+ or AO in rating, the parents blame the game for the violence and sexual theme rather than blame themselves.
When players sign up for a game, they are knowledging themselves to have at least looked at the setup first. If they sign up for a game without having looked at the game, them blaming the host should instead be countered by an infraction on the player because they're the one being toxic.
You play GTA5, you get what you expect - a "fun" game of driving, gangsters, mafia plotline, shooting.
Then you play WoW, you get what you expect - a MMO experience with thousands of players and boring daily quests.
You play Nier, you play an Action RPG as expected, but with Bullet Hell mixed into it, which is not what you expected at all.
See what I did there? Just because you buy something and have expectations, doesn't mean it has to meet your expectations.
Some developers like to change the formula, add their unique gimicks or try new stuff out.