Because it's a completely arbitrary number. The difference between what you think his avg is and 90 pts is 25 pts. Zetterberg has only put up 90 pts 1x in his career.
.
I saw you say "elite playmaking winger". Not so sure about that. I'd say Hudler also had a better hockey IQ and was a better passer.
Tatar is a better skater and more eager to score.
Your numbers are wrong. I said his absolute best season will likely be around a PPG, but if everything goes perfect, he could hit the high 80s/90. That's not unresponsible.
Yes, I think Tatar eventually turns into a playmaker and he could have the potential to be one of the better ones. His game suits a playmaking role. He draws defenders, and is solid at finding an open teammate. Right now he's shoot first, but I think later on his style changes a bit.
Hudler's passing is inconsistent. He throws some absolute awful passes. Hockey IQ, overall, sure. Hudler's best season was probably his last in Detroit (speaking in terms of Detroit) where he put up 25/25 and became a physical player (don't ask me how). Tatar could pass that within a year. Tatar eager to score is huge, as many of our players are not, well not at his level. Skating isn't great, but it's better than Hudler's (agreed again). Tatar's style could really mesh as a playmaker. He doesn't have some crazy shot.
Again, if Tatar played the entire season (close to it) he'd be on pace for 45 points right now. His first season in the NHL as an every-day player. That's damn impressive.