>Most personal mail servers are not going to be sending mass emails.
There's no way to tell whether a random host on some residential ISP or VPS provider is doing personal email or spam.
>An algorithm that auto-spam-boxes mail from domains it's never seen before (or only receives a small trickle from) is ignorant.
Since blacklisting is so prevalent, spammers who aren't idiots will be sending most of their spam from different IPs. They go out harvesting unpatched VPSes and Windows botnets. The latter is patched by residential ISPs blocking port 25, the former is still a problem.
>Maybe the big mail providers need to update their strategy regarding automatic spam-boxing?
Why? Almost all legitimate email is coming from one of the big mail providers or a big-corporate Exchange server. What reason do they have to let more spam into their users' inboxes?
There's no way to tell whether a random host on some residential ISP or VPS provider is doing personal email or spam.
>An algorithm that auto-spam-boxes mail from domains it's never seen before (or only receives a small trickle from) is ignorant.
Since blacklisting is so prevalent, spammers who aren't idiots will be sending most of their spam from different IPs. They go out harvesting unpatched VPSes and Windows botnets. The latter is patched by residential ISPs blocking port 25, the former is still a problem.
>Maybe the big mail providers need to update their strategy regarding automatic spam-boxing?
Why? Almost all legitimate email is coming from one of the big mail providers or a big-corporate Exchange server. What reason do they have to let more spam into their users' inboxes?