Grate n Colorful Oz
Hutson Hawk
You have to put the players in the same environement:
Mcdavid and Crosby in the 80s for example:
Wood sticks
Food
Not the same off ice training (plyo)... the players at the time barely trained in Summer
Heavier equipment (skates). My skates at 7 years old in 1982 were heavier than my adult skates now...
No video to help to improve your own skills.
Red line
Hooking ...especially in the 90s
Now put 99 and 66 in todays hockey.
Composite stick.
Modern equipment.
Diet food
Off ice training
My ranking for those 4 generational players in any era would be:
Lemieux
Gretzky
Mcdavid
Crosby.
Lemieux came back after 4 years retirement at 35 years old in 2000 with Hasek, Brodeur, Roy etc.. in net and Red line , hooking, dead puck era and the dude did....:
35 goals in 43 games... and 76 points.....
A martian.....
All your comparisons are worth naught, because the single biggest difference is the overall level of talent, and the difference is huge, which gives a lot less space to maneuvre.
It's just impossible to know which would be which as all are products of their own time with very different paradigms.
The only constant here is people always idolizing the past.