Its age of the core and quality at the time of creation. Youve gotta admit there's a big difference between a 31 year old garnett, a 32 year old ray, and a 30 year old Pierce vs a 26 year old lebron, a 26 year old bosh and a 29 year old wade.
Plus at the time wade and Lebron were both top 3 to 5 players in the nba.
Bosh was like top 10 to 15.
The Boston big 3 was great but none of them where top 3 players at that time and they were considered reaching the end
. Thats why they are looked over imo. 26 is too young to be forming Voltrons