Can you share some examples of spam you've been getting?

Nowadays, when I post a job for our openings, I get thousands of applicants, which is much higher than 2–3 years ago. Over 90% are irrelevant. To limit the applicant count, I ask for references. For example, just the other day a candidate reached out directly, I asked if he could provide references, and then heard nothing back. It’s the quickest way to filter out irrelevant candidates. Now I am employing the same tactics and building an ATS where references make you stand out.

Not sure if this will help, but you can try something like:

1: Make an email inbox just for the job opening.

2: Make a silly rule that the applicant must have a specific word in the title. It could even be random characters. For example, you could state "To apply, email applications to gdfhtrd@sgtfg.gr with 'ghubv' in the subject."

Then, make a rule that forwards emails with that specific word to your real email box and ignore the rest.