Captcha here will only harm your real users' experience and won't protect against this kind of abuse, since it comes from real scammers, not fully automated bot

Captcha here will only harm your real users' experience and won't protect against this kind of abuse, since it comes from real scammers, not fully automated bots. I've dealt with these and similar issues over the last 8 years, which led our team to develop a security tool 5 years ago that is now open-sourced. https://github.com/tirrenotechnologies/tirreno https://github.com/tirrenotechnologies/tirreno