That's a different issue. You're usually not notified of spam designations, but bounces (where the mail server completely refuses to accept your email) do usually receive a notification. If you're designated as both (for example if you keep sending email that bounces) you'll get blackholed and wont receive any bounce notification either.
When I used to self-host my emails, GMail would "accept" mails then drop them. Microsoft was kind enough to tell me they dropped them but getting out of the blacklists was a pain.
An advantage of landing in spam is that the user still has a choice and is in control. Rejecting outright is a "lalalala I can't hear youu!!" type of stupid situation that only big providers can get away with, without the users realizing their bigcorp is the one with delivery issues
Conversely, if you as the sender get a bounce at least you know something went wrong and can try a different way to contact the other person (different email, telephone, text message...) Bouncing is the traditional approach, and the original ethos was "bounce, or defer, or deliver, but don't ever accidentally or deliberately just drop an email on the floor".
It depends whether you think of "the user" as the sender or the re cover -- as a (human) sender I'd rather get a bounce than be silently ignored in a spam folder, but as a receiver I prefer the grey-area emails to be accept-but-spamfolder, not bounced...
As a user, I'm thankful I don't need to sift through hundreds of spam emails a day to find potential false positives. Because that's what you're advocating. You'd apparently like everyone to have a terrible email experience for the sake of your own personal comfort and preference (self hosting your emails).
Besides, for something truly important, the people or organisations who need to reach me know how to do so other than via email (phone, chat, postal mail...).
This. Microsoft, Google, et al. aren't doing anything worthy of criticism here; it's the spammers who ruin email for the rest of us who should be facing the music.
