Yes, it's annoying because mailbox owners have zero control too. If your brother in law complained to outlook that some emails are missing from his inbox/spam b

Yes, it's annoying because mailbox owners have zero control too. If your brother in law complained to outlook that some emails are missing from his inbox/spam because outlook decided to reject them outright, he would get the same respnse. "We have smarter systems(r) than your judgement, sorry." (Remeber, you can't click "not spam", if the e-mail was not delivered at all) The problem is the burden of not upsetting a mail filter got somehow shifted to the sender in case of big services filtering mail, which is ridiculous. Customers should talk to their providers if they're not receiving mail, because providers don't deliver it. But the correcting feedback loop is not there or/alternatively is much longer with more steps than in case of sender getting a bounce.