Maybe it helps that I pay for Google Workspace, but my pretty well known emails do not really receive that much "spam". However, it depends what you consider spam and I have a pretty strict definition to be automated junk/phishing messages I never consented to receiving. I also include non-"junk" mailing list messages (some semblance of not being a scam or coming from a semi-legit org) that I either never consented to.

I imagine for a lot of people they, unknowingly?, subscribed to a lot of things they don't end up caring about and never try to unsubscribe. In Gmail they can even automate this for you to some extent. And I am pretty sure they track that information and if a mailing list isn't respecting those unsubscribes their email is going to start being dropped entirely.

Consider the possibility they someone is subscribing you to nonsense? I think Gmail's filters work pretty well. In fact I am very surprised how well they work because for a while I was getting a ton of spam in the inbox and losing important messages (~max 3 years ago). Now I can't remember the last time it happened.