You are the first person to say that overall he was the fifth best prospect in the draft, and that only Arizona passed on him.
Absolutely it was common knowledge that San José, Columbus and Anaheim had to decide on whether to pass on Michkov as he was being touted as "the equal talent-wise to Bedard, etc".
If you truly believe he was 5th best, it's no big deal for a team that is drafting fifth and knows he can't come over for 3 years, and may never come for all we know, to draft the 6th best player.
If you don't think Reinbacher is 6th best, then argue THAT point.
If you believe Michkov is second in talent but all the question marks drop him to precisely 5th, who says another reasonable person can't decide they drop him to 6th or lower?
So back to this 1D / 2D thing. In my view, a first pairing D can play 24-25+ minutes. It is not a REQUIREMENT they be the PP quarterback. If so, then Serge Savard, who was never a power play quarterback, would be disadvantaged in your draft ranking system.
If Reinbacher's potential is that of a first-pair D who can neutralize dangerous scoring chances, win pucks back from the attackers, transition the puck back up well equally with his feet or with a pass, kill penalties very well, and chip in offence with good legs and a great shot, then he is Roman Hamrlik++ and Hamrlik was a 1-OA.
Myself, I don't think Michkov will be the 110 point player some dream of, unless he cheats and cherry picks his way to that personal stat and gets lucky one year in four. NHL defences are too good against a guy without an extra gear and without the muscle to overcome determined defenders. I will be thrilled if Reinbacher is a great shutdown/possession D tilting the ice for 25 minutes per game as we compete for a cup, while allowing Hutson or Mailloux to shine on the PP -- even if Michkov makes the highlight reels from time to time. It's an opportunity cost I'm willing to pay given the flaws even YOU see that drop Michkov to 5th in your eyes.
I see a bit of Alex Galchenyuk in Michkov. Good dangler but not fast enough to beat NHL defenders, yet who racked up points at the Junior level. Not the highest compete level, not the top 2% in attitude. Better shot and release for sure, Caufield-like even, but Caufield, while great to have on your team, is not a "generational player who puts the whole team on his back". Even in a re-draft, Caufield may not get picked higher than Michkov was. It's close in my opinion.
Really, I'm ok with the Habs thought process. The player performances over the years will tell the tale.