Now I know there are ton of different flavors in each of these tech but they will be mostly distraction for employers. With heavy layer of abstraction of above pattern and SLAs by vendors as you say Microsoft/Google/Amazon etc employers will be least bothered vast variety of software products.
At some point it'll become impossible to build stuff off platform because it'll have to integrate to stuff on platform to be viable. Your startup might theoretically be able to run on 3 servers but your customers' first question will be "does it connect to googazure WS?" and googazure WS is gonna be like "you wanna connect to your customers' systems? Pay us. A lot.".
There goes your profit margins.
Then, if your startup is really good googazure WS will clone it.
There goes your company.
GM/Chrysler/Ford didn't have to be better than the startup competition they just had to be mediocre + be able to use their market power (vertical integration) to squash it like a bug.
The tech industry is headed in that direction as computing platforms all consolidate under the control of an ever smaller number of companies (android/iphone + aws/azure/gcloud).
I feel certain that the mass media will scapegoat AGI if that happens, because AGI will still be around and doing stuff on those platforms, but the job cuts will be more realistically triggered by the owners of those platforms going "ok, our market position is rock solid now, we can REALLY go to town on 'entitled' tech workers".