like i said it's reasonable to drive for all at different points in the past but it's unreasonable to drive for all 4 at the same time. Think about it, incentive-wise, if you complete 50 trips you got $x , if you complete 100 trips you got $2x. If you only got 50 trips in you, why are you splitting them between two apps 25 trips each and got $0 incentive?
Almost every driver I ride with is switching between the Lyft and Uber apps to see which one is offering better rates/destinations. The incentives appear to be insufficient to offset rate disparity in this market - unclear if that holds true everywhere.
I'm not at all well-versed in statistics, but it seems that without enough extra cash to consistently one-up the competition in terms of incentive structures, a ride share company could not make the driver's choice of which app to use a non-random event. So yes, a driver wouldn't necessarily choose all four at once, but they also wouldn't consistently pick one.
It's a well known fact that the biggest factor in taxi revenues is how much paid miles/km you can do per day. The single biggest factor to increase your revenues is increasing that number.
So unless the incentives are massive, a driver will always look for the next ride by any means necessary. It's nearly never worth it to "wait for a better option".