You’re talking way too hyperbolically to take seriously.
Yes, GMail does, in fact, “have a clue.” They do pretty well. They’re not perfect, and I have specific complaints, but to pretend they’re totally clueless and inept discredits anything else you’re saying.
Just as saying that machine learning can identify spam discredits anything else ex-reddit CEO says.
I'm sure gmail have a clue from their point of view, but those doesn't align with mine (nor, I'd argue, most of their users). Their view also as a coincidence happens to strengthen their hold on the market but who cares?
So, how do they "solve" it? By using the "reputation" of your IP addresses and trust that more than the content of the email.