At the risk of wading into someone else’s quarrel, I would say that it’s only been 10 drafts since the 2015 changes; and if we consider the most recent four as too soon to judge the impact of a committed rebuild, there’s only 6 drafts to judge on, which is not nearly enough to draw any strong conclusions. Of the teams who have committed to a rebuild since 2015, both Edmonton and Toronto look like contenders this year. The jury is still out on New Jersey, and things don’t look great for NYR and Buffalo. Detroit, Chicago, Anaheim, and San Jose are more recent rebuilders so we’ll see how those go.
I agree with your premise that complete tear downs and rebuilds are less certain propositions under the new system, and they were never a guarantee before. Having said that, it also seems clear that teams need top tier talent you find at the top of the draft to win the Cup. So, you either draft it, or trade for it.