My point is that even if you isolate 3rd party APIs from your code there might be things that can't be "translated". Obviously both EC2 and DigitalOcean give you the same basic product, virtualisation (the greatest common divisor), but the "quirks" each one of them have are the ones you should be exploiting to get maximum efficiency, and this is generally non-portable.

But yeah, I think SaaS is a great way to scaffold or MVP your ideas. You can have a hugely complex infrastructure up and running in just a few clicks, but I don't think it's a great long-term solution.