Agreed, but like others have pointed out “marketing” includes marketing to drivers with incentives to drive. They’re not running advertisements they’re subsidizing rides on the driver and passenger side and calling it part of their marketing spend.
The problem with Uber is that their technology isn’t that innovative and their platform isn’t that sticky.
The technology only seems "not that innovative" because they've been around for a decade. The whole concept wouldn't be possible without widespread smartphone adoption which occurred in that time. The real problem with the business is the economics don't work. Riders use Uber because it's cheap and driver use it because they get paid enough to make it worth their while (or at least they believe that to be the case). These two things are only the case because they're blowing billions of dollars on subsidies.
The problem with Uber is that their technology isn’t that innovative and their platform isn’t that sticky.