That's a terrible idea in my opinion, any advertising at all on Wikipedia would be the thin edge of a very unpleasant wedge. Wikipedia is many people's first stop for knowledge, we really don't want people being able to buy eyeball space next to what's supposed to be unbiased content.

Additionally, expanding advertising generally is a bad move when exposure to advertising has been shown to be negatively correlated to quality of life and contentedness. We need to be transitioning away from advertising as a primary driver of the online economy, not fuelling it further. Advertising should only be employed when there's no better option in my opinion, not the first thing you reach for monetising a site. We should see advertising like fossil fuels, a regrettable necessity that we should aim to phase out.