Microsoft. It more than compensated for Azure not being the best product . They are incredibly more responsive, you have multiple points of contacts and escalation chain of actual humans you can meet
they will even come to your customer call or connect with their rep already working with the mutual customer and so on.
AWS has the best tech and but not as good as Microsoft service wise, they certainly improved a lot last few years and it shows but because they don’t have any enterprise apps like MS their footprint is more limited.
Google keeps talking about GCP being important but doesn’t feel anything has changed on ground
My company also used all 3 (at a very large scale / spends). MS was nice, but useless / incompetent technically. Anything non-trivial took forever to get a straight answer or resolve. We rarely got to speak directly to anyone with real expertise.
AWS, we could speak directly to Sr engineers on the relevant team. Full transparency, highly responsive. They were clearly trying to understand our issues and suggest change for both us and themselves.
Google was mostly useless. There was one team I got to talk directly to, who were great. But that was the exception.