I named lever-action rifles, as my go-to rifles, not because I am old, or old-fashioned, or because I dislike such modern weapons as the AR15/M4, but because I am VERY accustomed to some principles of firearms operation, and prefer weapon that operate by those principles, for “go-to” purposes. The safety/selector lever of an AR15/M4 is ready to FIRE when the lever is oriented perpendicular to the muzzle. If my muzzle is on-target, and the weapon is upright, that means the lever is pointed DOWNWARD. Notably, I got a much earlier start, by a number of years, with weapons that are ON-SAFE if the safety/de-cock lever is pointed downward. Later, I was issued Tasers with safety levers that operated in the Walther/S&W manner, and was required to perform a spark test drill at the beginning of each duty shift, which involved moving the lever off-safe to perform the drill, and then re-safe-ing the weapon. That is a long ton of Taser drills, over time, that reinforced the Walther/S&W pistol range sessions.
So, understanding a thing or two about human performance under sudden stress, I would rather that an AR15/M4 not be the long weapon that I first reach for, when I might be suddenly awakened, or suddenly called to action from my mind being deeply occupied with something unrelated to shooting. The cross-bolt safety, common to many shogun systems, is something with which I am VERY familiar, with a 24-year head start, before I first started training with an AR15. External hammers, in the case of lever-action rifles, and some single-shot rifles, were intuitive for me to use, a number of years before I started using an AR15. I owned an M1 Garand a number of years before I started AR-fifteening.
I know my way around an AR15/M4. For several years, after attending a regionally-well-regarded patrol rifle/carbine program, I was a designated “carbine unit“ officer, on police patrol, using a personally-owned AR15A2 Colt Govt Carbine. When the front sight grew fuzzy fur hair, I sold that one to a colleague with younger eyes, and later bought M4 rifles that could readily accept optics. I keep several AR15/M4 type weapons, but I do not keep them near at hand, in ready-to-grab-and-shoot condition. My nearest-at-hand, loaded long gun is a Benelli M2, one of my personally-owned duty shotguns, up to my retirement, six years ago. If the shotgun (or ever-present handguns) cannot solve the problem, well, then, it is time for the go-to rifle, described in my previous reply post.
Just edited to add: Now and then, I get new-rifle fever, and something about the “bush rifle” length (18” barrel) M14/M1a has become appealing, lately. Now, THAT would be a sweet go-to rifle, no? (Remember, I established early familiarity with the M1 Garand, so, would not be transitioning from scratch.)