[ItsDeathball]

"Normal people" have absolutely not stopped using imageboards. Perhaps they feel outnumbered on the boards specifically devoted to politics because every other venue for political discussion bans certain viewpoints, concentrating proponents of those controversial positions in the free speech platforms. That's only one portion of the imageboard use case. Most people are there to talk about anime, video games, technology, or whatever other esoteric hobbies drive them to seek Internet discussion; it's difficult to work in advocacy for fascism to those discussions without catching a ban for being off-topic.