Is it a good thing that this happens with Amazon? Probably not. I’m not sure what regulations would do.
But the general point is you don’t get all the amazing innovation without some side effects. Change sucks but maybe it’s not a bad thing if not everyone can be a third party retailer for Dyson vacuums or Samsung TVs, instead these people provide services that we need like airplane pilots, air traffic control, nurses, cops, and teachers.
You're assuming that everyone has the capacity to do these things. I think you're well aware the overwhelming majority of people can't.
I benefit greatly from the new style economy but I'm also aware that I was born with a Mathematical mind and I have advanced computer skills whereby my skills are in high demand. I am in a field with 'achievers' and they still can't do the things I do. The moral of the story is the mantra of 'learn to code' doesn't actually work.