No one's upset except for you. Sorry that your feelz are hurted.
When you make big claims before all of the facts are known then double down on them you should be prepared to be called out. Apparently you do give a f**k.
"The post IS NOT about what kind of gun it was" - You mentioned AR-15 twice in the meme, scroll all the way to the top, red background, white letters, made by you, remember?
You certainly have a loose relationship with reality.