If the setup is that portable you probably don't need the AWS at all in the first place.

If your use only services built and managed by your docker images why use the cloud in the first place ? It would be cheaper to host on a smaller vendor , the reliability is not substantially better with big cloud than tier two vendors, that difference between say OVH and AWS is not that valuable to most applications to be worth the premium.

In IMO, if you don't leverage cloud native services offered by GCP or AWS then cloud is not adding much value to your stack.

This is just not true for Terraform at all, they do not aim to be multi cloud and it is a much more usable product because of it. Resource parameters do not swap out directly across providers (rightly so, the abstractions they choose are different!).

...if you don't have much data, that is. Otherwise, you'll have huge egress costs.