Hmm.
Hmmmm.
I want to say 'yes' but, quite honestly, I often end up super powerful and grow bored of the game without ever completing the main quest. I never beat Skyrim, despite starting over twice and being a virtual god on earth each time. I never completed Far Cry 3 or 4, despite taking all the bases and towers and unlocking all the weapons and doing pretty much everything I wanted to accomplish. I did beat Fallout: New Vegas, but not until like my third character.
However, I think having events that keep pulling you forward while opening up new content are important. There are times when I fire up FC4 where I just want to go out and have fun and other times where I want to work toward a goal.