If one were to accept the premise that DT is being overrun by alt accounts, which I don't think is a valid assumption, and if you were to ignore the value of privacy the forum gives its userbase, the OP's solution would not solve his stated problem. A simple google search returned several VPN services claiming to provide residential IP addresses for customers, and it would be difficult to filter these IP addresses as belonging to a VPN. There are also devices such as mobile hotspots that someone could use to get around any no alt account rules.