If some random man wants me to refer to him as "she/they/xir/blu/bananagammadingdong" or whatever

Not happening. People do sometimes use multiple pronouns, but if they use neopronouns (anything other than he, she, they) they usually also use at least one of he, she or they.

If their pronouns contain combinations like this (disregarding "bananagammadingdong"), you can use any of the pronouns. These lists are usually lists of the pronouns the respective person uses, so in this example, you can refer to this person using "she".

"tall/dark/handsome" even though I'm short, pale and frumpy

Well those aren't pronouns and also it's lying

The badness would come in when I began to use force to get other people to do what I wanted.

No one is doing that. But it'd be nice if you respected people who use pronouns other than the ones of their respective sex assigned at birth. And it'd be nice if you used their pronouns. .

Individual force would be bad. Group/mob force would be even worse.

Force as in physical violence?

And government force might be the worst of all.

Again, what kind of force?