He played 4 games of SANFL last year, and started in the SANFL this year after missing the whole pre-season comp and the start of the season proper with a hamstring injury, which I would consider mitigating circumstances.
I don’t disagree with your point that playing state league isn’t inherently a negative reflection on a player, I just think your example of the Crouch brothers is way off the mark. Especially saying Matt Crouch only broke through this year. He was a fixture in their team all of last year, and one of their leading ball winners. If Langford’s 2017 had been Crouch’s 2016 (22 games, 27 disposals and 4 clearance a game), this thread would quite rightly be nonstop lid off.
The reason I’m arguing about the specific case rather than the general point is not because mids that aren’t best 22 within their first few years don’t exist (eg Seb Ross as Noonan points out), but because they’re not very common, and I think it’s important to acknowledge how uncommon it is, especially if you discount players who’ve been substantially injured early on.
Obviously if you see “it” in Langford there are examples to show him becoming a topline mid from where he is now isn’t unprecedented. But I think it’s reasonable for people who don’t see “it” to be at least concerned that his career from here will be like most players who’ve had similar careers to date.