I think Reagan (who I disliked then and still think he's one of worst US presidents ever) would have crushed Mondale regardless of the assassination attempt. Mondale was a horribly wooden candidate. Think "Al Gore without the sparkling personality and lovely wife." Sarcasm aside, Mondale had absolutely zero charisma, and Reagan had it in spades.
Reagan got very lucky, similar to Trump and Teddy Roosevelt. If Hinkley had been "successful" we would have had President Bush 8 years sooner.
Interesting...Bush Sr. had been head of the CIA and is the only major political figure who claimed to not remember where he was when JFK was assassinated. I never thought of that connection to Reagan until today.
Not just BTW, there is also VERY credible evidence that it was Bush who orchestrated the takedown of Nixon because Nixon continued to investigate the JFK assassination.