Pronouns, and ideas like "non-binary", embolden people to subvert gender, and are a tool to subvert gender
No they don't - a non-binary person isn't asserting that the binary doesn't exist, they're just placing themselves outside of it, and therefore implying that the rest of us are binary.
If a person says that they're a special type of non-binary person who uses 'they' pronouns, what are they thinking about someone like me? Who is totally fine with admitting that sex exists that it's a binary, that I'm a woman, and that as an English speaker, people would generally refer to me as 'she'? In what way, apart from those above, must we differ in order to justify their 'non-binary' as something other than self-indulgent snowflakery?