It fact you absolutely shouldn't as this put them in huge conflict of interest.

how will you investigate corruption if your funding can be cut?

What issue from the listed above public funding would address? Public funding doesn’t prevent the entity to become bloated.

I bet we could come up with a list of things we don't like about adtech, tax those behaviors, and give the proceeds to their local competitors.

That's a radical idea! Unfortunately, it gives a lot of ammo to the "anti-socialist" people who are vehemently against anything "public" funded by tax payers. Look at what's happening in the Nordics for example, where pretty much everyone supported public radio/TV at least when I was growing up, but nowadays a bunch of political parties are trying to have it removed/reduced.