I think it's the nature of an endurance event.
The end of Le Mans isn't that exciting either, the teams often wait for each other down Mulsanne & cross the line together in formation. It's the spectacle of the stage though, the riders charging up & down the Champs Elysees, the sprint finish etc.
I'm sure if it had been close yesterday, then it would pan out differently & they would have raced right to the wire. The hard work goes in over the whole 3 weeks. Like the Champions League, if you're top of the group, they play a weakened side, the hard work's already been done.