It tends to happen more on front end I think, especially since it's in the tutorial and many haven't been given the training on what to do better. Not really AWS, but even the trained ones will put it in a .local.properties file or something and then forget to add it to gitignore
In a ideal world yes developers should care about these issues but developers need access to AWS keys to locally test integration with AWS services like SQS and Dynamo so access to micro service keys needs to be provided.
The problem occurs when they forget and commit, that key needs to be rotated which has caused downtimes in the past, or scrubbed which involves a messy fight with VCS support teams.
The problem is not just AWS, in general for third party integrations with platform like banks developers needs to test locally but they forget removing those keys. Each keys committed is a potential SOC2 / PCI non-compliance avenue.
You never need to have your access keys in your repository or read them explicitly from any properties file. The SDK will automatically get the keys from your home directory when you run your code.
There is no sample code from AWS that has you read access keys in your code from a .local file. The SDK automatically picks it up from your local environment when you run AWS configure to store them in your home directory or better when you get temporary credentials via the IAM identity center and store them in environment variables
You really just need to not forget to do that. Isn’t it that simple?
A less snarky answer, and why AWS is largely a non issue these days is because the secrets were designed out of code And are effectively provided as an integral part of the infrastructure which includes regular and reliable expiration and rotation. So any chance you get, design secrets in this way.
The only thing ever in code are references to the correct roles or secrets. Only ever references to the location of the secret. Get in the habit of this and the problem is drastically reduced and becomes something you don’t have to think about.