Nah, it looks more like when you see an old college friend in their 30s who's mostly aged well but just gained an extra 10-20 lbs and you can't see it on their gut yet but their face looks just slightly rounder and their neck/throat slightly looser.
Yeah think it's a "white guys" thing because Bird was a post who could play outside also and Luka is a big wing who might even have been considered a guard 20-30 years ago. Luka's most similar to Tatum right now although not as good on defense. Historically, it's hard to say - James Worthy? John Havlicek? George Gervin? Paul Pierce?
Luca is sort of in a class by himself. He's big, 6'8" and strong. He's not skinny, he is bulky! He pushes small guards around and no one--big or small-- has shown they can stop him down low because his moves are incredible and unpredictable. He is creating on the move. His step back jumper seems to have no limit. It's pretty accurate from 30+ feet and deadly from 15 feet on in.
He seems to be working on his defense, thanks to Jason Kidd, and that is noticeably better.
I think he needs to stop jawing with the refs so much--leading the team in technical fouls is nothing to be proud of.
He is, at 23 years old, arguably the best at his position in the NBA.