I dont think people are being gleeful.
Notice how this reaction is common both in the right and the left.
It is because people realize there is a deep injustice in the US and you yourself highlighted it.
Some people are fortunate enough to get the highest quality care possible, while others.....just die.
For example, it is 100% evil to cancel a woman's insurance, after she is diagnosed with Uterine cancer using a spurious reason such as failure to report acne.
So we in Canada may have to wait 1 year for an MRI, but when the shit hits the fan, I can assure you that Canada provides the highest quality care that is comparable to just about any developed nation out there.
Our doctors, nurses, hospital staff, ER staff are all truly great.
I have myself been a recipient of such care just this past year.
For non urgent cases, yes we all wait.
And although that is not efficient, it is still JUST.
That is what people cheer for.
A CEO that led a company with a 32% denial rate, that financially ruined families and destroyed lives, was gunned down.
Not sure for what reason.
People like him do whatever they want, and always get away with it.
Doesn't matter how evil or immoral.
But considering the amount of lives he negatively impacted, his shooting would appear to be poetic justice.