For better or worse (Apple keeps making it worse), I use Apple Mail for my email. But Apple’s junk mail filter is buggy and still sometimes blips on when disabled; it’s buggy even when disabled!
Enter Michael Tsai’s SpamSieve, which I’ve used for some years now. With a little training, it’s highly effective at passing through the good stuff and blocking the unwanted stuff, which I can quickly skim just in case (no filter is ever perfect).
SpamSieve is indispensible for my high volume email needs!
A point driven home regularly by Apple: every time Apple Mail changes, Apple intentionally disables Apple Mail plugins. But with SpamSieve, an update is promptly made available, generally within a day. I value that kind of support strongly.