All major aerospace companies and projects are heavily subsidized in every country otherwise they would never survive or even be born. Like how much profit did NASA make over its lifetime?

I'm very surprised the EU and the USA and SpaceX didn't work out a deal to buy a certain number of F9's to be launched and operated from the EU. The EU would pay a (vey high) price to buy outright the rockets, and would agree not to develop a competing rocket design in the next 20 yrs.

Isn't the whole point of Ariane to maintain European capability for independent space launches?

It would be very hard to spin that up from nowhere after twenty years of complete inactivity.

That’s not the only alternative.

It doesn't seem that surprising given the terms.

So the worst of both worlds? It would still be very expensive, but also dependent on a foreign entity and with hands tied for the next decades unable to develop people, skills, or products in that direction.

I mean it makes sense, why not sell off rockets and whatnot commercially like the mass production strategy that Musk has in mind? But I don't think there's enough launches yet to warrant that. In fact, SpaceX is booked full for the next few years already; unless that's intentional, they simply don't have the production capacity to humour that idea.

ESA is never going to just buy a rocket, because that would completely defeat the point of ESA.