And, if you're running your own mail server, there are hash based blocklists that list spamming email addresses, including Gmail addresses.
@spamhaus &
@abusix both have such datasets.
Very easy to integrate with spamassassin, rspamd, mimedefang, etc.
Do it do it do it do it do it! Sick of people using Gmail to spam you? It's soooo easy to report them to Gmail! Here's how.