There are definitely good adaptations that can come from the longer length endurance rides. Generally speaking, riding 2 or more hours opens the window to adaptations that are new and unique when compared to the higher intensity workouts under 2 hours.
We discussed this at length in the Polarized Training threads (3 total). There is true value in the “long and slow” ride if you can fit it into your schedule. Others can summarize better than I can, but you can skim those threads to see some of the related discussion (I can provide links, or you can search on the “polarized” tag).