Managed Postgres.
Let me know if there are any others that you feel strongly about?
It'd be great if you can share how to best spin up a managed Postgres instance.
I'm using GKE and it has been working like a charm so far.
I do not remember to have read about Google equivalent of EFS yet. This can make it relatively easy to migrate legacy apps to cloud.
And as the other comment says above, familiarity. We have around 20 programmers at our company who are comfortable managing deployments on AWS. We had to spend a lot of time and money on their training. Google hasn't given the 10x reason for us to switch.
I don't want some 3rd party to manage Postgres. I want something seemless like RDS.