> Building trusts with behemoths like GMail or outlook.com is too involved
There's nothing like that actually. I have e-mail server running since 2000s. When gmail appeared, everything continued to work as expected and it did for many years. Around 2018 or 2019 I noticed that my e-mails started going to spam folder. I didn't send any bulk e-mails, I was not on any RBLs, I was not compromised (I actually was very careful to block outbound SMTP from any user except the one running MTA), and of course had SPF & DKIM set up.
It looks like their spam filtering is just arbitrary and feels like done on purpose to discourage running personal mail servers (and looking at comments it works really well).
Honestly, I think some kind of campaign is needed to put them in place, like starting blocking e-mails from gmail (maybe responding with a message encouraging to switch account). I remember in the past steps like that were done, but feels like today people are more acceptable of centralization.
They certainly are discouraging from running small mail servers, because it's harder to hold a small installation accountable. A spammer is usually a tiny installation which would disappear overnight, being run on random botnet nodes.
I don't think they explicitly are trying to quash smaller independent mail servers (personal or commercial), they just see what spam statistics show, and update blocking rules accordingly, maybe fully automatically, using ML. The fact that they also quash small-time independent competition is just a nice (for them) side effect.
They operate since 2007, they can track who is reliable and who is not. It's not like IPs change[1].
[1] yeah, they might be some people trying mail servers on dynamic IP, but I'm not talking about those and Google would have some justification not categorizing them as reliable. I'm talking about using business level ISP offering with a static IP address and matching RevDNS.
There's nothing like that actually. I have e-mail server running since 2000s. When gmail appeared, everything continued to work as expected and it did for many years. Around 2018 or 2019 I noticed that my e-mails started going to spam folder. I didn't send any bulk e-mails, I was not on any RBLs, I was not compromised (I actually was very careful to block outbound SMTP from any user except the one running MTA), and of course had SPF & DKIM set up.
It looks like their spam filtering is just arbitrary and feels like done on purpose to discourage running personal mail servers (and looking at comments it works really well).
Honestly, I think some kind of campaign is needed to put them in place, like starting blocking e-mails from gmail (maybe responding with a message encouraging to switch account). I remember in the past steps like that were done, but feels like today people are more acceptable of centralization.