Every "outrage" in the US consists mostly of shit people don't understand. That doesn't mean they're wrong about the cause, but you can be "right" for the "wrong reason".
In this case, yes, DoorDash employees are getting screwed. At the -same time-, DoorDash is doing nothing weird or outside of the norm.
The solution is wrong. People are trying to get 1-2 companies to make tipping a little less bullshit, when its tipping itself, across the entire country, that is broken.