A simple way to filter out bogus accounts is to require KYC. If an account has been verified, they have greater posting abilities. If they haven't been verified, they are in read only. This seems like it would weed out bots and spammers!
Now if multiple account create from a single ip then it stays on read only mod. So, I think your desired think is already on the forum. Though it is on another way. KYC can be bogus as now a days there are a lots of people who can edit any data. Also it is not a paid site. And many accounts being created each day. TO check these accounts need many workers but it requires payment. Where forum is free then how will pay them. Also there is an another thing, block-chain created to keep users anonymous if forum requires KYC then it will be alternate way to invent the block-chain system.