AWS to Google Cloud. Already mature product (public company). Many potential customers are strongly Amazon-averse. Switching to GCP won some deals that were being lost otherwise.
Anybody's cloud strategy should try and stick to the most basic services/building-blocks possible (containers/vms, storage, databases, queues, load balancers, dns, etc) to facilitate multi-cloud and/or easy switching.
Not that each cloud doesn't have its quirks that you'll have to wrap your head around, but if you go all in with the managed services you're eventually going to have a bad time.
I concur, in my experience the biggest driver of growth for Azure and GCP is that customers of SASS companies and consulting companies make it a requirement to choose anyone but AWS. Legacy companies are terrified of Amazon.
Google does have some innovative big data products like BigQuery and Dataflow. In general choosing GCP over AWS shouldn't hinder a companies growth at this point IMO.
Amazon sell a lot of stuff and consequently compete with a lot of legacy companies:
Brick and mortar retail in nearly all fields (fashion, food, tools, appliance, books, etc), other online marketplaces (often with a mail order past) and even some tech companies.
Generally, companies are unwilling to give money to their competitor, reinforcing it.
They also might want to avoid some PR issues, as using your competitors product can lead to juicy stories depending on the situation/field.
If they are somewhat paranoid, they can also be reluctant to have their data accessible by their competitor (and I'm not talking DBs access there, even something like ELB logs can give valuable information, iirc such story did pop a few years)
Working for a marketing SaaS solution, requests from our clients to not be hosted on AWS are still quite common.
Apparently Walmart and Target stay away from AWS but most of it seems to be FUD regarding, I guess, Amazon potentially targeting their competitors and their suppliers to steal data stored in AWS/use it for strategic business moves. It would be a swift death for AWS if they were found to be doing this, though, so imo the fear is unfounded.
Netflix is hosted on AWS to name just one such instance. I have heard that internally the customer names are obfuscated, including other Amazon services. Indeed it would be a death sentence to prioritize themselves.
Anybody's cloud strategy should try and stick to the most basic services/building-blocks possible (containers/vms, storage, databases, queues, load balancers, dns, etc) to facilitate multi-cloud and/or easy switching.
Not that each cloud doesn't have its quirks that you'll have to wrap your head around, but if you go all in with the managed services you're eventually going to have a bad time.