I would disagree he ends his career a failure. He ends with a legacy in the name of himself and his father who survived the track. And will forever be remembered for that.
God bless his journey forward.
His sponsorships are the end product of his father's popularity. He is a failure in the sense that he never achieved the championship or success he was expected to. For this Kevin Harvick blames Jr for the declining interest in NASCAR.
Let's compare Jeff Gordon and Senior to Junior in the Monster Energy / major professional Series:
Gordon: 25 years, 805 races, 93 wins, $153.7 million in earnings. Win %= 11.6%
Senior: 27 years, 676 races, 76 wins, $42 million in earnings. Win %= 11.2%
Junior: 19 years, 631 races, 26 wins, $95.7 million. Win % = 4.1%
As you can see, OBJECTIVELY, he never lived up to his expectations and did not earn the popularity or following he has.