Imo mocking the term they use ("pronouns") harms the cause. Mocking incorrect usage of the word doesn't do anything but provoke eye rolling. They don't mean literally all pronouns and they know we know. Mocking them like this just gives them an easy out and makes uncertain readers feel like they're not being taken seriously, thereby pushing them towards the right.
As to not having neopronouns "back in my day", a lot of neopronouns are surprisingly old. Ze is from the 1860s, hir from the 1920s. Even relatively new ones like xe have been around since the early 70s.
And they may be pointless for you, but they're valuable to some people so why be rude about it?
Something existing for the sake of existing does not make it useful.
I think the point some people try to mke is that they should be free to use the pronouns they seem fit. Forcing someone else to use language they are not comfortable with is just as rude.
"Let me use whatever language I want!" "Nope! That is rude!"
Both sides being rude.
