Could it be... ?
Could it be that modern (for their time) military weapons inevitably (?) become widely accepted hunting weapons. If we take a quick trip down history lane, the Mauser 98 which is now the epitome of "classic" hunting rifle, started life as the quintessential "assault rifle" of two World Wars (and a few others), not to mention the Mannlicher that was for a brief time its military contracts rival, nor the British Lee–Enfield which was the Empire's response and found favor too in the colonies in civilian (or even military) attire...
Same goes with cartridges by the way. The 30-06 and .308 world acceptance as hunting cartridges likely owes a lot to their military pedigree, not to mention the 7x57 and various 6.5x5X, nor the .303.
So, I am not overly surprised to see the "modern sporting rifle" growing ascendancy, although I speculate that this was a major endeavor by manufacturers to find a new market and a new legitimacy for their hardware when "black" became less fashionable and less socially acceptable than tree-bark camo ;-)
Where, in my mind, the concept reaches its limits...
1) In order to be as accurate as quality bolt actions, the AR platform guns need to be considerably heavier (11 to 13 lbs). Border line prohibitively so for walk-around hunting, I would say (although I do carry happily an 11 lbs 4 oz .340 Wby for days on end while plains game hunting, and most of us find perfectly normal to tote around 12 lbs or so all day when buff hunting).
2) I can hardly think of a situation when semi-auto high-volume fire is needed / desired in a hunting scenario (culling is likely different).
3) The instant availability of (many) follow-up shots inevitably invites "spray & pray" with many who have not learned the benefits of slow aimed fired while wearing government issued fatigues (and even with many who should know better, yours sincerely included).
This being said, I love mine and I shoot literally hundreds of M118 and .308 Win Match 168 gr BTHP Prvi Partizan Ammo (PPM3082), and .223 Rem Match 75 gr BTHP Hollow Point Prvi Partizan Ammo (PP54) every year at 12" steel to 600 meters with the .223 and 800 meters with the .308 with a pretty high hit ratio. The .223 works fine on prairie dog towns too, but I have yet to find something requiring the .308 power and sustained fire.
Top: Armalite M15 20" Target .308 Win rifle. 13 lbs 2 oz. Genuine 3/4 MOA with 173 gr M118 balls and a number of 168 gr match ammo. Almost as good, but not quite as consistent, as my Steyr Mannlicher SSG69, which is no faint praise...
Bottom: Wilson Combat 20" .223 Wylde 1/8" match barrel in Rainier top on Colt Match lower with Timney trigger. 11 lbs 12 oz. Genuine 1/2 MOA with a number of 69 to 75 gr match ammo.
Note the stock-attached ballistic tables, mil rad external turrets scopes, and bipod spigot hand rests on each gun, which betray their role as long range tools (toys).
Yep, I can probably provide fairly secure flanks with those, and if given the opportunity would endeavor to provide such from enough of a distance and with enough movement to mitigate some (most?) of the effectiveness of the volume of fire from the average platoon of most modern armies...
PS: by the way, if you have not tried PPU ammo, regular or match, give it a go, you will be amazed at the cost/quality ratio...