The data you linked doesn't show that. If I were on my computer, I would download crude oil prices/US shale oil extraction data and look for correlations.

My intuition seeing this is that the lack of openness of Venezuelian economy made it impossible to recover from the crude oil price drop circa 2014, because of a lack of access to capital and new tech (and probably corruption). Also, if you want to nationalizes, you better have a plan like Norway had, and Venezuela didn't. If your goal is only profit, better let a private company take care of it, that's the thing they're good for.