Yes, but 15k emails...

It would have to be a fully automated / AI system that attempted to scrape sites for contact emails, look up domain ownership if possible, and even guess emails (info@<domain>, contact@<domain>, support@<domain>, etc.)

I guess this is exactly what WHOIS information is meant to provide, a way to contact the owner or administrator of a domain. Of course many sites today rely on WHOIS anonymization, but legit e-mails should still hopefully make it through to the owner.