What’s wrong with creating a barrier to new entrants? If it removes all the shadchanim who shouldn’t be there to begin with and prevents new ones who don’t belong there from coming in- that’ll be a win for everyone. The few who belong there won’t be ashamed to refer to themselves as “shadchanim” (and won’t have to deal with the riff raff), those who are forced out can pasture elsewhere and do something productive with their lives, new entrants who didn’t want to be part of the riff raff could get certified and help those who can use their help and finally- the singles who need them the most would know where to turn.
I love your idea of a place where victims of shadchanim could leave their negative comments. After hearing countless times “stop being a chenyukkel, you need to tell me why you said ‘no’, there’s no Issur of Lashon Hora by shadchanim”- it would be nice to give them a taste of their own medicine.
I can’t see the shidduch process being automated. Finding one’s bashert is much more complicated than purchasing a plane ticket, especially since a good part of the time the person themself doesn’t fully understand or know what they’re looking for. That’s why we could use “professional” shadchanim, those who were able to join the profession by getting by the barrier and are able to live up to a strict code of ethics.