My guess about the US is summed up in the phrase "Follow the Money".

If you want diversity in offerings, you have to have diversity in the
way the money (as little of it or as much of it as there is) is
controlled / doled out / obtained / provided / earned.

In the US, there are really only two mechanisms: advertising and public
aid (as on public radio). The former drives things in the direction of
the lowest common denominator or in the direction of the most flagrant
and outlandish and is highly coupled to what is hyped as "in".  (The key
is to establish "coherence in the market place" so you have all
consumers moving in the same direction so you get as much audience share
as possible.)

The latter sets up a game with rules that, I am guessing, depends more
on politics (as in who do you know -- not the R and D and whatever kind)
as to who and what gets played.

If the above theory is correct, then it would predict that in the EU if
there is more diversity of offerings, there would be more diversity in
the way the money is controlled / doled out / obtained / provided /
earned.  Is that the case?

--D.