I don't think it's reasonable to expect ride share companies to pay their drivers a fair wage when they are in fierce competition with each other and self-driving cars are on the horizon.
I agree "mandatory" tipping like in US restaurants isn't a great system. I don't think including tipping in an app with a default of $0 makes it close to mandatory. Lyft could give stats on what fractions of rides have a tip given; my bet is it that it's relatively low. Making optional tipping easier is a good thing.