[njonesuk]

In AWS, accounts within an AWS Organization are roughly analogous to projects within GCP. Most organisations running AWS in production will have tens or hundreds of accounts managed within their Organization. Segregating by security groups hasn't been the recommended approach for years, for this reason amongst others.

The accounts and Organization model is a slightly clunkier abstraction than projects, but on the other hand the security boundaries between accounts are harder than those between projects, which has its benefits.