You're definitely not a Monday Night Q on this take but Panarin is not an issue per se, or at least not the hinge pin that you make it up to be of what went wrong. The issue is that Lafreniere, Kakko and Kravtsov (and Andersson) all failed relative to expectations based on their draft positions. Drafting is not an exact science but this is some horrible bad luck (and while I fully acknowledge that drafting Lias and Vitali wasn't objectively a given, Alex and Kaapo were universal choices).
The other issue with your argument about alternative vets signings in place of Panarin - it would be far from guaranteeing that this plan would work out as in after 3-5 years of rebuilding the team will come out on the other side and make playoffs. I'm not going to list all the examples again, you know their story.
The last piece of mismanagement was organizational decision on McD. I can't help but look at how LA kept Doughty through their rebuild. With hindsight re. how McD held up physically this was probable the biggest "outgoing" blunder.
I'm not even saying that the alternative would have worked, but they sent out a letter saying that they were going to set out in a new direction and basically took the exit ramp before the trip even got started.
What we do know is what they did failed and the decision to sign Panarin is one of the bigger reasons why.
I don't know that Laf or Kakko would be game changers even if they had been given the opportunities and usage that most 1 and 2 OA's get early in their careers, but I do know that you don't get better at doing things by not doing them. At the very least, It would have been nice to see both of them not get passed over for PP time in lieu of Ryan Strome and Colin Blackwell.
Lias and Kravtsov were f***ing failures. They were able to make up for Lias somewhat (he was traded for the pick that turned into Cuylle who is a good player) but yeah, Kravtsov was a miss and a half and a total f*** wad. Kind of blending this convo into one thats already existing, but the 2017 draft was seen as a super weak one outside of the top 5 or so, Rangers picked 7th.
There are like 5 or 6 guys chosen in the following 10 picks who have all turned out to be very good or great players.
2018 was considered to be a better draft. Almost all of the forwards (and players really) post Kravtsov also kind of suck.
Anyway, a lot of good players have been traded since the summer of 2019. It would have been nice to have the surplus assets (and cap space) to use to land a few of those guys.
Instead we got Panarin and kept most of what was already here. Don't need to rehash what Panarin has been in the playoffs as a Ranger, we've all seen the games.