Could you maybe elaborate a little on how a domain checker would have helped with the topic linked above?
The OP doesn’t include a domain, only an email address. It was your response in post 11 which referred to a .com, which incidentally is a valid registered domain - it’s parked at sedo. Had the user specified it and the domain been checked it would have returned valid whois information.
I’m not clear on how your proposed solution would have reduced moderation burden in the topic that you linked.