You're still missing the point.
Easy and instant access does not cause a person to consider murder. Easy and instant access makes it easier for a person considering murder to successfully carry out their desire.
I think your point defeats your point. If I'm considering - planning - to murder someone, you're simply moving the date of the murder to a future date with waiting periods. To effect your end, it would be necessary to forcibly remove guns from the population and remove the ability to murder via gun. Your assumption is the person will not be murdered by other means or the future acquired (after waiting period) gun by the person
plotting murder. Which, last I knew, is illegal.
A common example is 'crimes of passion' or IPVs - Interpersonal Violence. Ordinary, normal people in practicality do not suddenly snap and whack their wife but are the culmination of a history of domestic abuse.
Which begs the consideration of the multitudes of people who are spared death or serious injury each year by having the means to protect themselves. What of them? Will you have police dispatched round the clock for their protection while you delay their right to not become a victim? Of course not, it is an impossibility. The fact is, nothing levels the offender/defender playing field as quickly and with more utility than a firearm. While the 2A simply acknowledges - not grants or establishes - the necessity of not allowing government a monopoly of force by acknowledging a right to 'keep and bear arms', it is the primal (as in 'of first order') right to defend oneself against unwarranted aggression that is the basis of the amendment, whomever the aggressor may be. The Bill of Rights is overwhelmingly a distillation of the sound ideas evident in state constitutional conventions that preceded the national. In both we find this primal right discussed, as well as other lawful activities involving firearms.
Oration has always been the first foundational weapon of every dangerous movement and the totalitarian; Stalin summed it (sic) as words/ideas are more powerful than guns; if we would not allow them guns, why would we allow them words and ideas? Until recently, we understood that risk inherent to 'free speech' is necessary to preserve a constitutional republic And if that ability to attempt peaceful reconciliation with government failed, then the next amendment at least protects the fighting chance to reclaim it. Speech rights have degraded to the point in other Western countries, that in practicality it is a facade having not been given the constitutional protection that is unique to the U.S. How did the left come to so devalue both the 1A/2A rights that they no longer wish to respect or retain either?
What waiting period for our liberties shall we have government establish to protect us from them or our murder plotting fellow citizen?