It's weird to describe this as "employment" when many and perhaps most drivers these days are simultaneously "employed" by both Uber and Lyft, serving rides for both. This kind of informal relationship is a lot closer to contracting than traditional employment.
It’s perfectly normal to have two W-2 employers.
On the other hand, it’s odd that these “contractors” can’t set prices for their services and risk deactivation if they decline the price Uber offers.
Is it quacking like employment? Sort of and sort of not.
Not: very flexible hours, not exclusive, driver can switch customer? driver provides tools
Is: driver cannot subcontract, has to follow set rules (maybe that makes is franchise like?)
Of course they took something that was employment and made it not employment at scale.