I'm not debating Michkov v Reinbacher. This is a non-issue for me and probably 90% of posters on here. If Michkov is there, you pick him.
To your point though, how many true elite RD are there in the league? I encourage you to try and count them, you'll probably be surprised. I have:
Makar
Fox
McAvoy
Hamilton
Karlsson
Seider
Montour? Pietrangelo? Burns? (Not even sure)
And then a group of RDs that are either good but non-elite, or old: Letang, Ekblad, Doughty, Carlson... It's at least on par with 1C in terms of rarity. Again, my point is:
If you believe Reinbacher can be part of that 1st group, then it makes sense to pick him at 5, if Michkov is gone.
I personally think his most likely outcome is the 2nd tier, which is why I wouldn't pick him before Benson.