Good eye.
It was shown in several episodes that Walt’s career in chemistry was limited due to a combination of arrogance and poor treatment of others. His relationship with past colleagues is strained and he snaps at a past flame.
Ultimately, it seems as if he wasted his life and talent due to his own poor character. He just never broke the law as large and clearly as he is doing during the show.
His bitterness over ‘wasted talent’ ends up transforming into hubris over the success of his product.
He’s in the Empire Business, and thinks he’s untouchable. Classic story of someone too smart for their own good.