Gmail also dumps a lot of non-spam emails into its spam folders.

The ones that drive me nuts (and have led me to having to sign up to fastmail for my business emails, rather than sending from my own shared server) are the ones that are valid responses to emails sent from GMail in the first place. Excellent logic (or lack thereof), Google.

I don't actually believe so, but I have often wondered whether GMail has such an overly fastiduous spam filter simply to encourage people into its fold... .

Gmail can do that because they can see into the inboxes of many million of people. So if a mail is flagged as spam somewhere, it can use that info as a signal to classify it as spam in my inbox.

That is not the content based plan for spam PG describes.

And it comes at a cost. Complete loss of control over your inbox.

Switched from gmail because receiving too much spam. Part of the reason seems to be people using my generic name as a fake email address when they sign up for stuff, probably credit card promotions and the like. Wonder what it would be like if I used a custom domain with gmail. But not going back....

Ironically I run my own mail-server, and the majority of incoming spam I receive is routed through gmail.