Might not be as many as you'd think, a lot of those guys just find something else to do with their lives. Can't expect them to wait around forever
A lot of the 195+cm kids that don’t get drafted don’t really get the chance to physically mature in the state leagues. Many of them can’t compete physically at state league level as 19 year olds.
They end up playing a few games, but for the vast majority then end up playing local footy or reserves if they are based in SA or WA.
Sam Paea is a good example, was on the fringe of getting drafted last year, signed at Werribee but didn’t get much of a chance in the seniors because he lacking 5-8kg to really be a force. Ended up playing most of his footy this year in the EDFL for Aberfeldie. You aren’t getting drafted from there.
Josh Rentsch is another one. He was on the fringe to get drafted last year, ended up going over to Sturt in the SANFL. Played mostly reserves, managed a few senior games but avg’d less then 10 disposals and a goal per game because he is playing on a lot of ex AFL listed 26+ y.o key defenders.
Then the lure of $$$ from country and metro footy usually means a lot of them walk away from state leagues before they reach their potential.