@zaitcev @arcana @sun @newt @scathach @mold The trick is to set up DKIM/DMARC/SPF properly. If you are low-traffic enough, you won't get put in the spam folder. What also helps is sending a legitimate looking email (not something like "This is a test" to a burner gmail account that has existed for some time and if that get's sent to spam, manually flag it as non-spam.

There are some theories that they use some arbitrary ranking system that checks things like IPv6, DANE, MTA-STS and (START)TLS support and rank those MTAs better, but I've never been able to verify any of that.

The thing with Gmail is also that a lot of legitimate mails from reputable providers get sent to spam anyway.