You seem to be under the false impression that 4chan makes money, as in, is profitable. It's very much not. Nor does advertising, much less UK advertising, constitute an important influx of money into the "business".

A rather strange conclusion from my words. I do not assume it’s profitable, but it’s pretty logical that a for-profit organization running a service that is based on user engagement will have its revenue from the sources linked to the audience, be it advertising, subscriptions or donations. If you cut a visible slice of that audience, it’s going to impact the revenue. It’s still not profitable, 10 years after acquisition? May the investors be blessed for their charitable attitude, but it doesn’t change anything.