I think it’s effective. I have an email list where I somehow got random contacts through a form of a popular content hosting platform where they didn’t combat a

I think it’s effective. I have an email list where I somehow got random contacts through a form of a popular content hosting platform where they didn’t combat against spam emails nor verifying them. When I send newsletters, those email addresses will mark my emails as spam although they aren’t. That makes my email provider lock my account if there is enough reports of spam to the point where I had to remove many emails from my list that I had no clue otherwise. Majority of those emails were gmail accounts. Thus I think about my experience every time I mark an email as spam. I assume the spam you’re talking about however will just cycle through reputable email providers to get into your primary inbox since the filters are hit and miss.