@mark
My hosting provider is hostmonster, which a tech told me supports literally millions of domains
Clearly they don't. What it sounds like they do support is a few spammy customers by using a million others (including you) as human shields. Why you'd defend this practice is baffling. There are countless things they could do to actually support legitimate users, not the least of which is compensating the victims. Abuse coming from your network range is costing me money; make it worth my while to have my system do anything more than drop you into a blacklist.
@Thunderbird
I think it is a reasonable expectation that I should be able to send and receive email if I want to.
Google, almost certainly the largest email provider on the planet, disagrees. Whether or not their users have that expectation is another matter. But the fact remains that people keep using large email providers despite these unintended harms. I mean, I've had times when a Gmail user sent me a message, and then the idiots at Google dumped my response into the Spam folder.
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