phpMyAdmin is great when you're first learning to work with the LAMP stack; it lets you fiddle with values, manually create databases, munge columns, etc.

But.

If there are multiple instances of your system running "in the wild" (even just within your own company), and their versions will ever have even the slightest chance of getting out-of-sync? You really want the entire change-history of your modifications to the database checked into git. You want to be able to take any previous sorta-known database state, and move it toward the current well-known database state. To do that, you need programmatic migrations.

And as soon as your software ships a "db/migrate" folder, (non-readonly) phpMyAdmin access becomes anathema to proper configuration management.

AWS can be thought of as a big database that contains your EC2 instances and snapshots, your S3 buckets, etc. At scale, you only want to interact with this database programmatically.

So: if this was the correct hypothesis for why the GUI sucks, what would be an expected prediction? That the programmatic APIs for manipulating AWS would be great.

And they are! All the HTTP APIs for AWS--the ones you would use in any automated provisioning script--are simple, clear, and pain-free. They're definitely the "first-class" road to AWS, documented to heck, and it's clear that Amazon itself dogfoods them directly.