It's hardly dismissive. If there's a lack of unions in a field, how does that problem get resolved? By starting one.

Sure they could provide more resources and information , except oh wait, someone else literally a post above did.

No one ever said starting one is easy, like anything worth doing it's a LOT of work, but that's a complete different matter than the comment being "actively unhelpful, [or] dismissive"

Edit:it was the same guy who posted the comment with more information. Maybe instead of you being actively unhelpful and dismissive, ask questions about the process, seek help, and don't just dismiss what someone else said.