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Ad revenue while it does convert free-service users to dollars isn’t the only means of commercialization (traditional business subscriber models for one) and as long as any financial incentives are there (not just ad-related), there will be spam of all kinds. Any general purpose medium will be come subject to this, it’s inevitable.
To the large point, a very very small amount of users have the means, capability or desire to host their own networks and services. Raising the technical bar means lowering the audience size. Even then, you’ll still find bad actors and people you don’t agree with.
They did this on Top Gear (or Grand Tour maybe, can’t remember). Personally, cooking doneness aside, I wouldn’t want some exhaust leakage from the engine or burning oil that’s seeping from a gasket to taint the flavor of the food even if there were a guarantee of no carcinogens from it.