So I get the feeling that you're used to arguing by just being overbearing and smug but that doesn't mean that you actually win the argument at the end of the day. Just repeating "prove it, prove it, prove it, prove it, prove it" makes you sound like a broken record without a single original thought of your own and no understanding of basic reason or scientific method. You don't "prove" something is true by positively showing it applies to 100% of cases, you do it by testing it against all other cases until there are no exclusions left. If you want to show I'm wrong and try to convince people here all you need to do is name a law and show me a state where it was implemented with a resulting reduction in mass shootings. The thing is, you can't, which is why you're just repeating the same thing over and over and over again.
As far as the far left like CNN and MSNBC causing them, it really doesn't take much to show their impact on it. Virtually every criminal psychologist agrees that they do it for the infamy and attention and vehemently disagree with the current standard practice of reporting on them. The liberal media literally takes the exact list of "what not to do" by the experts and does just that every single time and, as the study I linked shows, this has been blatantly linked to repeats and copy cats.
As I said in a previous reply, there is a simple legislative fix here, but it goes directly against the 1st Amendment freedom of press so unfortunately, until CNN grows a conscience and decides they care about stopping mass shootings more than they hate Republicans and guns, we're going to keep seeing these pop up from time to time. The real world solution of just having basic morals and being a decent human being isn't even novel. Cable news shooters boil down to a very fucked up version of public suicide; virtually none of them expect to survive and those that do are almost always because they chicken out at the end. Suicide has been known to be contagious based on publicity for decades and all major news networks have developed a standard of reporting that reduces this. Unless it's a celebrity (where they ignore this which leads to copy cats) you never see a news story about "Bill Smith was found hanging in his closet Thursday night after committing suicide." They always use careful phrasing along the lines of "Thursday night Bill Smith was found dead in his home, no foul play was suspected." A similar standard phrasing that does not name the attacker while reporting the basic facts of value to the public and de-glorifying the shooter would fall right in line with this. Unfortunately, they don't want to solve the issue so we still have this. Religious based and terrorist goals would still be an issue but even without guns mass killings are always possible by anyone with enough commitment. Bombs and car attacks have the potential to be far more lethal than a single shooter in a public setting but the current trend of suicidal losers trying to get the cable news high score a meaningful change could actually be made by not fucking giving them exactly what they want while creating a motive for others that try every single time.