McDavid is a generational talent.
Eichel is not a generational talent. Eichel may or may not be a franchise player. Yes, Eichel is superior to Reinhart (which doesn't mean much).
To sacrifice so much and be so close to McDavid and not get him would be an incredible disappointment. They wouldn't "tank" for Eichel.
I'm basically repeating myself now so I will stop.
Even if Eichel is "just" a Stamkos- or Tavares-level prospect, that's just about the greatest thing to happen to this organization in the draft since Perrault. At the end of the day, the numbers don't lie, and Eichel has put forth the best draft year college freshman season in the last couple decades. That's nothing at which to thumb our noses.
As for the "they wouldn't tank for Eichel" comment, the irony is that is precisely why they're tanking--to assure themselves of at least Eichel. If Eichel's not in this draft, Murray doesn't tank to the degree that he did.