An important distinction is that T-Systems (a subsidiary of Deutsche Telekom) is not a subsidiary of Microsoft. AWS EU on the other hand is presumably still a s

An important distinction is that T-Systems (a subsidiary of Deutsche Telekom) is not a subsidiary of Microsoft. AWS EU on the other hand is presumably still a subsidiary of the American Amazon Web Services Inc the same way Amazon EU S.à.r.l. is a subsidiary of Amazon proper. Since AWS EU presumably shares the same infrastructure as AWS US it's probably more of an accounting trick (but keep in mind any GDPR fines would apply to the entire group, not just the individual corporation, so it's not really a financial protection).