Instead of a large group of low power, easily manipulatable and controllable workforce, you will have traded for a small group of very powerful, wealthy and influential business and tech people who now fully control the production of your labor. I'd be very worried if I was that business, in terms of the control that company would now wield over me.

They could release a software update and disable your entire workforce unless you agreed to pay more money. They could slow your workforce down to prop up a competitor, etc.

It will likely end like cloud computing. So, not amazing, but certainly not what you describe.

Your current cloud provider can absolutely "release a software update and disable your entire workforce unless you agreed to pay more money". The reason why they don't is quite obvious (competition).