The latency difference between a UK based and an EU based Data Centre is trivial for nearly all use cases. But the price of electricity and cost of cooling is significantly different in other countries.
If you actually need high performance and low latency then you build your own DC on site.
My own company provides IT services via the AWS (Amazon) cloud.
Most customers choose Ireland for the DC even though they are UK based. Makes no difference to user performance and the e EU location ticks the box for data protection concerns.
However we also use DCs in USA (Oregon) and Japan (Osaka) and there is literally only milliseconds in the speed differences (latency) to the EU locations.
Ireland did pretty well as the tax haven for software companies due to low corporation tax and other incentives. It’s really the only reason why Dublin even has much of a high tech industry.
But it was a strategy that paid off for Ireland. Lots of jobs as a result of the high tech infrastructure located there.