He was pissed at his doctor and blaming the doctor for the ongoing pain...he wasn't cooling off.
54% of gun-related deaths are suicide. Those typically are not committed through the use of the evil and much-maligned AR-15. 43% are murders, of which only a very small percentage are "mass shootings." Instead, they are committed by criminals doing criminal ****. You aren't going to find 10% by going after long-guns. You won't get 10% by deciding after more than 60 years that the age for an AR-15 or other long gun needs to be increased.
We ALSO have a smaller RATE per 100K than we had almost 50 years ago. That's right, more people per 100K were killed by firearms in 1974 than were killed in 2020 (the year where you got your number from).
People like you are strangely silent when, for example, a Tesla on auto-drive crashes and explodes into flame. But because those are something that happens and makes headlines, there ought to be the same clamoring to ban them because "OMFG...HEADLINES." Instead, the rational heads prevail and recognize that it was the idiot, not the tool, that that caused the incident.