Because US-in-EU is fake-EU.
CLOUD act, PATRIOT act etc. etc. US headquarters doesn't escape the arm of US law.
Remember a long time ago there was a famous case where Microsoft fought the US DoJ when they came looking for somebody's data in Azure Ireland ?
That was then. Now is now. Do you honestly think Microsoft would put up the same fight today, especially if the US President decided to lean on them ? I don't !
CLOUD/PATRIOT etc. has gone from a theoretical risk to a real one. And now you have a US President in office who doesn't care much for bypassing all that anyway.