IP blocking won't work at all. Many countries don't offer fixed IPs to regular internet users and even those that do will be bypassable with Tor or even a regular proxy. Banning by range will exclude a lot of legitimate users.
I'm also *deeply* against requiring users to fill out any personal info on their profiles. Just because you are comfortable giving out RL info doesn't mean everyone is or should be. There are different realities across the globe and you really shouldn't judge everyone according to your reality. I do appreciate anonymity on public forums, specially ones related to devices that are regulated in a huge chunk of this planet. And, as a last point, requiring the info would not guarantee people are telling the truth, specially those that want to do bad things.