>>19167
Here's my opinion.
The imageboard format helps everyone to tell whatever they want. I don't know if this was the intention when the first board software came out, or they just wanted its use to be as simple as boiled potatoes.
A format that needs registration might help, but they could just register over and over again. Or implement pre-moderation - every post would be reviewed and allowed/denied, but that also work for the staff just at different place (reviewing instead of deleting), plus they had to review posts of everyone, and allow manually...
4chan bans every VPN and proxy, and disallows Tor. Problem is many users can't post, especially not from countries where people are blocked by their ISPs or a certain office of communication.
It doesn't matter if a spammer does his crap by the power of autism, or he's getting pay for it, these will do it no matter what.