The AR went from a 2 position colapsible stock, to a 3 position, and finally a 4 position for the military. In the civilian world 6 position stocks became standard. Other stocks, like the 8 position UBR Gen 2, offer even more adjustment options.
I remember when I build my first AR15 that I wanted to have as much adjustment as possible in the stock. Now I find it silly that I own a SR25 with a 10 position receiver extension and I only ever use 2 positions of those ten.
Now it certainly not bad to have more stock length options, but I wouldn’t pay a premium for it now.