I have never had this issue. Generally the issue is either IP reputation of your server (common with VPS providers if you get a recycled IP of a previous spammer) or your domain name.
Otherwise you are probably just unlucky enough to tickle the spam-prevention mechanisms in the almighty "algorithm" run by $BIGMAILER.
I keep one "normie" email address at a $BIGMAILER for situations like this, but at this point in my life I mostly just shrug if some big advertising/surveillance company's email system won't deliver my mail, I just won't email that person.
I have never had this issue. Generally the issue is either IP reputation of your server (common with VPS providers if you get a recycled IP of a previous spammer) or your domain name.
Otherwise you are probably just unlucky enough to tickle the spam-prevention mechanisms in the almighty "algorithm" run by $BIGMAILER.
I keep one "normie" email address at a $BIGMAILER for situations like this, but at this point in my life I mostly just shrug if some big advertising/surveillance company's email system won't deliver my mail, I just won't email that person.
Be the change you want to see and all that.