You data nitpicks extremely hard.

7% of the guns purchased are used in crimes but doesn't mean those guns were used by the person who legally purchase them (firearms are stolen frequently by not properly securing them, this is an education issues). You still have 93% of the crimes you're overlooking too.

Three quarters of guns used in mass shootings were bought by the shooter legally

This is nitpicked data, that journalist defined mass shootings as when 4 or more people were killed, where as there were many many more mass shootings that would drastically reduce that "three quarters" amount.

Kyle Rittenhouse simply borrowed his friend's AR15 before crossing state lines to intimidate and antagonize protestors.

This tells me all I need to know about your thought process. I'm glad he was able to protect himself with it. There's a reason the charges were dropped, and you'd know this too if you watched the trial where the assailant admitted to attacking Kyle and pulling a gun on him.

The majority of homicides use stolen guns, and over half of those were stolen from vehicles

Again, education issue. Having a much harsher screening program will help drastically reduce this.