When creating thread, another additional option should be available and that should be something like; No Signature
What this feature will do?
If someone replies to a thread, his/her signature will not show up. Basically it will be empty.
Which, as signature spammers slowly realize that their effort to spam certain threads is not working, they will put their focus on other threads they can spam and this will create space for quality discussion at certain subs/threads.
You can make your own self-moderated threads where you delete posts made by spammers. They won't bother posting if you make it clear you'll delete their posts and you actually follow through.
Theymos already added two boards that are signature-free --
Ivory Tower and
Serious discussion. As you'll find out, they aren't very active. Take from that what you will.
If you're into price speculation,
the Wall Observer thread hides signatures and moves really fast.
I think it's the shitcoin/token-paying campaigns and their managers that are the problem, because it's pretty clear that most of them couldn't care less about post quality.
I think so too.