Part of being an employee is that your employer can dictate hours. You are ofcourse free to negotiate otherwise but if it's a minimum wage low skill position you don't generally have the power to do that.

It's important to remember that companies will always take the maximum they can get away with for the least compensation.

In the current situation that is asserting some control over the drivers to disincentivize them declining jobs but fairly little else because to exert more control would invalidate their claim their drivers are independent contractors. This is beneficial to Uber as they don't need to pay payroll taxes and provide health benefits etc that are tied to employment in US. i.e the overall cost to Uber per km driven is probably lowest this way.

The moment their drivers become employees there is no benefit to them not exerting all the control they can under an employment agreement. For instance there will no longer need to be a system for surge pricing because there won't be a need for surge compensation for drivers to increase supply because now the drivers are employees you can schedule shifts to ensure demand is met with sufficient supply.

Will it lead to a large portion of Uber drivers no longer being able to drive for Uber? Most likely. Will the drivers that remain be better off? Most likely as they were probably already full-time but not receiving benefits. Will ride prices go up? Most likely. Would this be better overall? Maybe, it's not as clear cut as a lot of people are making it out to be.