I am a consistent VPN user. One of my pet peeves is that a majority of websites flag VPN users as spammers, which is unfair, but completely understandable as most spammers will of course, use VPNs when their main IP has been flagged/banned.
So, on sites like Wikipedia, Facebook, etc, it is difficult to sift through and filter the spammers from the non spammers, especially if both parties are using VPNs, even if it is for different reasons (For me, it is for privacy reasons. For spammers, it is, well, to spam)
I believe crypto has offered a great solution to this. For example, on Bitcointalk, TOR users aren't outright banned, as they would be on any other forum of this size. Instead, you use crypto to verify your pseudoanonymous identity, after which you'll be allowed access, and will be allowed to post.
As we progress further, I think the ability to sign messages to verify identity will allow for sites like Wikipedia to open up editing to VPN users as well (Yes, there are many issues with this right now, but we could resolve them with time, I think)
But what makes you think that people who want to do spams will register themselves , would they use the loopholes or some other software which is allowing them to do whatever they want without doing the KYC?
Unfortunately the government is the only body that can enforce such things like , mandatory KYC for even sending messages and as you can see it sounds very ridiculous for the people who engage in the marketing and all.
It is a good idea but it lacks the implementation strategy.