I've had similar frustrations to the author.

We tried watching the broadcast coverage. Though I didn't time it, it felt like 60% advertising. This sounds hyperbolic, but it was really blocks of ads interspersed with highlights of events and (awful) commentary the majority of the time, and then occasional full events focused on very specific sports (swimming and gymnastics). I was shocked by how bad it was.

So, wanting to watch actual events, we paid for NBC's online service. It's an incoherent mess with login loops, and it still doesn't seem to include links to many of the full events, just the same highlight reels. It may be there, but after 20 minutes of searching we just gave up.

NBC has butchered this event.