I think you're missing the point. It's not a case of whether a country produces vaccines or not, as obviously they don't, but their attitude towards free trade. If they prohibit the exporting of products then that's a bad thing, regardless of whether it's done by the UK, the EU, or the US. If the UK hadn't introduced limits on what AZ could do with vaccines produced at their factories then they would have been exported, but they did introduce them, so they haven't been, just as America is limiting the trade in any vaccine-related products made on US soil.