Come on - nowadays most domains are non-".com"... .

That's not even remotely true. I've worked in cloud/web hosting for years and 99% of users are using .com domains. Yes more new users may be registering ccTLDs or gTLDs but that's generally because they're cheap. And because they're so cheap it creates a nuisance as spammers use them. Look a the .xyz tld. It gives you a hugely negative score on any sort of mailbox spam scoring algorithm.

I used to keep statistics on this, although I don't anymore. I remember seeing one day that not a single e-mail I received was a .info domain was legit -- that is, 100% of e-mails received from any .info domain was spam.

No idea if that's still the case, though.