This seems very much a situation of "public interest shaming", as the cheating directly harmed the legitimate runners of that marathon, and the marathon community has a legitimate interest in shaming/punishing/expelling caught cheaters (in addition to simply removing the fraudulent result) as a deterrent to potential future cheaters.

It's similar to disqualifications for fraud or doping in most sports - you don't only remove the current result, you disqualify them from some future events as a 'punishment'/deterrent.