Taxis were notoriously bad. They'd intentionally take slower routes to run up the meter, refuse passengers trying to go to locations the drivers don't want to go (despite this being illegal), etc. Not to mention this is all made more attractive due to our failing decrepit subway system.
The smartphone app innovation you speak of was not inevitable. Taxis indeed had a monopoly, and thus had absolutely zero incentive to developing an app. The competition induced by the ride sharing services destroying them is what incentivized them to finally launch an app, but I don't have it on my phone nor do I know anyone who has, and it's probably inferior to that of its competition.