Is this game huge or is the completion percentage tracker just broken?

I am level 28 and a half, 21 hours in the game, just got to the Jakobs Estate on Eden-6, been doing all side quests and all map challenges as I go. The in-game stats say I’m at 34% completion. That seems extremely low considering my level. There can’t possibly be 2/3rds of the game left can there? I would hit level 50 from the first playthrough alone if that was the case.

The game is huge. From my casual estimates, it’s about 25-30% longer than Borderlands 2 campaign. Arriving at Eden-6 puts you at about 40% of the way done. Completing Eden-6 puts you at about 60% of the way done. Very minor spoiler: Eden-6 is a massive story arc and I still consider it to be just 20% of the game.
I finished the campaign at level 40, after doing about half of the side quests and estimating it took 30 hours.

Wow, that’s alot bigger than I expected. Seems like I will probably be high 40’s at least when I finish the campaign then.