You need to take note that IP blacklisting will affect all countries or the VPN location used. Let us take this an en example, you use service provider A to open an account on this forum, some other people also use service provider A, and they are permanently banned, this will affect other people that wants to open an account on this forum from that country that are using service provider A as the IP addresses if service provider A is blacklisted by this forum. Also if it is VPN, the VPN per each location that the banned people are using to register account will be blacklisted.
I get your point, and we are still on the same page here.
I can be in a particular location and use a VPN to appear to be in another location, which means that the VPN that changes my location can also be used to create multiple accounts. When those accounts all get knocked out, I might end up giving that location a bad reputation, which could possibly make the location blacklisted.
But I don't think getting an IP address blacklisted is done just by 1-4 accounts getting banned for rules violation, I guess is far more above that, their should be a huge number enough to drag the attention of the admin.