They call it “dark traffic” - ads that are not seen by tech-savvy users who have excellent ad blockers.
Not surprised that its growing. The web is unusable without an ad blocker and its only getting worse, and will continue to get worse every month.
I use a degoogled CalyxOS phone so all those apps that load ads via Google services don’t even work, or they work and the ads don’t load haha. One caveat is that I can’t use paid apps either though, I’m not against those.
But yeah system wide blocking is definitely the most thorough method!