I used to run a fast twist (7) 22-250AI set up for the 80-90gr .22's. They're troublesome things and I remember having to walk back loads when the jackets started coming apart right out of the muzzle. Don't remember the velocity. Great for accuracy. Boring for performance. A fast .22 belongs to "exploding varmints". The last varmint I popped with it was a crow at 481 yards with a 90gr JLK javelin, IIRC. It just stopped walking and never moved again. d:^)
A 24” barrel is great at the range but not so handy otherwise. The current trend has been towards shorter barrels and collapsible stocks. It makes a handier platform but it also ends up robbing velocity from the 5.56mm cartridge which is very much dependent on velocity for its lethality. So, what we need is a way to improve the terminal effects in the short barreled ar15s and there are a number of ways to do that but the 22 Nosler may, IMO, be the most reasonable way to accomplish this task. It’s typical to poo poo new cartridges even when they are superior to the cartridges they seek to supplant. We have our reasons for this, brass/ammo availability for example;however, no anount of poo pooing changes the fact that the rounds are, in fact, superior. Personally, I have always liked the idea of a 22-250 AR but offerings were quite limited so I see this round as being a useful round. It fills that niche nicely- perfectly even. And, as yiu said, it can be necked up to accommodate, for example, 6.5mm projectiles which would also be very interesting.