Google, on the other hand, has had to build these relationships from scratch with it’s only advantage being advanced software and infrastructure which reduce costs.
Disclaimer: I work at Google opinions are my own
I've seen the AWS vs Azure vs GCP drama play out a few times, once on a team with significant Microsoft legacy and twice without. In my judgement, the MS legacy, even at its most potent, was a smaller consideration than Google's unmitigated weakness, every manager's worst nightmare: the concrete risk that Google would cancel something and the manager would get blamed for not seeing it coming. Maybe I've just been blessed to work at non-dysfunctional companies where non-technical management asks the opinion of technical management on technical matters, but technical management is highly cognizant of this risk and has been for a decade.
My recommendation would have been to go on offense. Make AWS's constant over-promising and under-delivering a meme. Make Microsoft's we-have-altered-the-deal-pray-we-dont-alter-it-further enterprise pricing a meme (compare to: google and gmail are still free). Build counterveiling fears in that technical manager's mind, no lying required, because Amazon and MS earned those criticisms and they earned them hard.
Now it's probably too late. Too bad. So it goes.
It has a reputation for killing cloud products like classic VPNs in GCP too, a significant part of our cloud infrastructure. Distrust is earned in this case.
App Engine did launch earlier, but that was not a general purpose AWS competitor.
Cloud compute is an even starker example: Google lost the second-mover cloud space to Microsoft and they lost it because the relevant decision-makers knew Google's reputation.