I am sure they do. However, speculating about the long run is my profession, so I'll do it.
As of now, it takes two seasons to create 2 reasonably skilled players for sale, given all the suboptimalities of the system. This is a gross estimation, but I am sure it is somewhat accurate. Assuming all teams do something similar, they are all looking to stock the remaining 3 positions, so the count isn't there. There will be a chronic shortage of players no matter what.
Of course, this is all irrelevant if the plan is to have the game stocked with an endless amount of players within the strong-proficient range, since a lot of teams seem to go for turnover rather than quality at this point. Which simply means that 10 levels of skill will be remaining vastly unused
"I don't know half of you half as well as I should like; and I like less than half of you half as well as you deserve."