I don’t think roll out speed of vaccinations for covid will have a great deal to do with devolution to be honest. It’s probably more to do with the Pfizer vaccination being the most prominent at the minute and that it’s the one that causes the most logistical difficulties. Therefor its easier to roll out in big conurbations and a bit more difficult in big areas of lower population. And Wales and Scotland both have a lot of the latter and proportionately less of the former compared to England.

Wales and Scotland have both vaccinated c 4.8% of the population so far and England and Northern Ireland seem to be doing better with c 6.2% and 6.6% vaccinated respectively. I’m sure that there will be big regional variations within those figures though - I doubt we here in the Yorkshire Dales are being vaccinated at the same speed as London for instance.

All that devolution has done is to separate and isolate regional variations between the countries

(That said, it was a twattish statement from that welsh minister)