In some countries, business addresses aren't considered PII (private information). I, as a business, regularly get emails because of the Whois, as well as I rec

In some countries, business addresses aren't considered PII (private information). I, as a business, regularly get emails because of the Whois, as well as I receive letters which I dutifully send back to sender, but the law doesn't identify the latter as spam. Is it the case that emails to businesses aren't spam?