This feels like working really hard to solve a problem that isn't yours. Why not just get your services from a company that will support you? Why is GCP worth doing this for?
EKS sucks. AWS data offerings outside of RDS are not as good as Google's.
AWS hierarchy also sucks. GCP projects/folder mechanism is vastly superior, also org policies.
I've also found integrating access controls via IAM to be really powerful and also pretty user friendly. In one experience, this helped us scale the sales process and allowed us to easily address sales push-back on data security and compliance.
Also, engineers really seem to enjoy using the cloud console, even at later stages when it was mostly just read-only and had a lot of access controls. The UX is just way better than AWS.
As mentioned, I've experienced issues with GCP and there are reasons to choose AWS instead. I can expand on these if anyone is curious, but wanted to list out the reasons to use GCP, as I feel like most of the posts you see about GCP on HN skew more negative than my own experiences.