It's a pyramid scheme. 32 teams and one has to finish last. That opens them up to fan critics..pure math
Fans have VERY little info to "inside" info like family, gambling, politics, intangibles, etc.
It is all hearsay info and hindsight info 90% of the time
Fans also have NO knowledge if a team is playing the 5 year game or a 2 year game
There also is no fair in public opinion...like when Hoffman and Karlsson's spouses get into it. These are intangibles, There is no formula that predicts a player like Ladd falls off a cliff while Chara keeps playing. Pure hindsight after that
LA won a cup or 2 without offense..while CHI won a cup or 2 without centers
Fans don't know sh*t, they only react to moves
You make some good points.
Some moves that teams/GM's make have a multitude of variables... and many of those variables are chaotic/unknown/random. Injuries happen. Players get married and other "real life" circumstances change. Players age, their bodies can't keep up and they gradually (and sometimes quickly and drastically) lose their skills. Covid-19 sweeps the planet and affects EVERYTHING. Exchange rates between US/CAD change... often drastically because of external factors... ie oil prices, debt levels of nations etc etc.
Many of these variables/factors can't be predicted easily if at all so I get the argument that hindsight is certainly 20-20 and even then... if someone says they should have done x and y and z instead of u and v and w... the butterfly effect means that it's likely unknown if those alternative actions would have resulted in any better end results than the original path taken.
A good example is the exact chain of events that transpired for years leading up to where the Oilers finished in the exact position to get the McDavid draft pick at #1 overall... if even slight changes occurred... Connor McDavid would certainly not have been an Oiler so yes to get McDavid they needed that level of incompetency from Tambellini/MacTavish/Eakins etc to be able to land in that exact spot to get McDavid. Any other chain of events likely would not have lead to McDavid within the organization now... and for that matter likely not Draisaitl either.
Would the team have been worse or better off NOW... if they had had better GM's, better coaches, better drafting etc for those years before they drafted McDavid, Draisaitl, RNH, Yakupov, Hall, Nurse, Puljujarvi etc. Possibly and possibly not.
They might still have been a middle of the pack "average" team spinning its wheels perpetually... always a playoff team and never a contender. There's plenty of those teams in the NHL as well when only 1 team in (now 32) that can win the cup each year and 31 "failures" each year as well.
I guess my point though is that fan participation IS a large aspect to what makes the sport popular (and what keeps fans engaged and spending money watching the games, buying merch etc). If fans didn't have an innate interest in the goings on in their teams... and that includes online/offline criticizing/critiquing players/GMs etc... and didn't spend the mental energy (and their dollars) on the game of hockey... then this game wouldn't generate the billions that it does and instead it would likely be a periphery sport like CFL football which will never attract the best talent and will never be able to put the best quality players into action each game and won't ever make their players into millionaires like the NHL can and does.
The owners/players/coaches/GM's (and the fanbases themselves) of NHL teams have to put up with and accept that fan interaction (and critiquing/criticizing) is all a part of the sport and is why there is the level of popularity and engagement that there is for NHL hockey that helps generate those billions of dollars that line the pockets of every owner, GM, player, scout, coach etc.