I have also been an Apple and tech user for a very long time, likely 4 decades, and that brings up another issue - pretty tired of the condescending tech support that have less knowledge about the topic or Apple's products, or their underlying technology than I do. At one time it was possible to have rapport and get problems solved. In the stores, too.
Regardless, this is quite literally the first time these issues have appeared with Apple mail, and yes, I am well aware of 'how spam works'. I will also send messages to Apple.
The modern hardware is great; the rest of Apple is on par with the rest of the modern Valley, i.e., woefully inadequate. Steve may have unwittingly brought this about himself when they created the iPhone (which relies on the same underlying technologies some of these folks are ignorant of, but c'est la vie).
Anyway. Please address this, Apple, and involve something that isn't an algorithm at some point in the process.