Edit: I'm not sure I buy the proposed argument that in a way, "the EU believed in the free market and fair play too much, and the US and UK betrayed those noble ideals", but I do believe the EU failed to recognize and/or counter the state of play, that the US and UK had legislated production partners and output to stay within national borders.
I think the EU even today is still boasting about how they saved a few euros on the vaccines. Such an great deal, when someone else pays for the consequences.
There are two issues: UK and US nationalism preventing companies to shift finished products to the EU in case of production troubles, while the EU has been slow to impose restrictions in the other ways. This meant that when the AZ plant in Belgium got production problems the EU had to take the shortfall alone instead of it being distributed on all customers: the upshot of this is that UK has simply gotten more vaccines than the EU.
The second problem is largely national: some countries have been slow to use the severely reduced deliveries they have gotten (possibly because their schedules were screwed up by the shortfall). The national governments have been really happy to pretend the national programs are perfect and there aren't large stockpiles of unused vaccines in their countries, and to blame all the tardiness on the shortfall "from the EU".
Nationalism? The Astrazeneca vaccines was paid for by the UK 3 months before the EU.
Not 3 weeks, 3 months.
The same production problems with the EU batch happened to the UK one, as far as I know, but they had time to fix it because of those extra 3 months.
Now the EU want to jump the queue and give it out "evenly", because it suits them. And if the shoe was on the other foot, they'd be saying 'je suis desolé, we have no vaccine for you British because of Brexit'. And you know it.
Plus they've been talking down the British strategy so much now their own citizens are wasting what Astrazeneca supplies they do have, so it'd be a complete waste.
The EU appears to be of the opinion that it needs to net export 8 million vaccine doses a month to the UK (plus 17 million to other countries, although the article doesn't detail if any doses are imported from those countries).
Cue HN complaining how much "bureaucracy" and how much "red tape" the EU has, and smth smth socialism.