I think the idea entered the popular discourse around public universities providing designated, debate-free spaces on a public campus which certainly seems like

I think the idea entered the popular discourse around public universities providing designated, debate-free spaces on a public campus which certainly seems like government censorship. Tensions were exacerbated because those universities frequently tried to reserve those spaces specifically for students of certain identity categories (obvious discrimination), and they were also trying to create designated "free speech zones" on campus, suggesting free speech was not permitted elsewhere.