I did, in fact, read all of that. You by all means bring up so extremely relevant points.
I was primarily referring to Boostio and stax, two players which come to mind as having excellent aim while still having to call for teams with extremely nuanced playbooks. I feel that in general the trend towards IGLs bottom fragging is less necessarily because their aim takes a massive hit when they are calling, but more towards the fact that their raw aim just wasn't necessarily that good in the first place but they were still valuable enough to be on a team because of their gamesense and comms, etc.
I think Marved also did a bit of calling on Optic and Faze, two of his previous teams, and learnt a lot under FNS so I don't think it's very fair to say that he's completely new to the IGL role. Also, from what I remember of Marved's gameplay it was less crosshair placement and more just quite crappy sprays towards the end of the season. He also said himself that he's a more chill IGL, ie. less micromanaging (as I referenced earlier) so I don't think that his fragging should take as much of a hit.