I watched all the interviews live on Celtics Post Game last night. Pretty sure Kyrie was referring to Tatum, Brown and Rozier when he said he's not necessarily doing the role he would selfishly want for him to get as many shots as possible or score as many points as possible but he's trying to do what he needs to do for the team as a whole to be better and to celebrate other players' success as if they were his own. The implication being that it's not just the young guys being told to play lesser roles.
It's obviously easier for Kyrie and Gordon to subordinate themselves for the good of the team because they've played in the league for years and made names for themselves. We have young guys like Jayson who has been anointed an All-Star and future MVP and feels the need to live up to it. Then we have someone like Jaylen who until last year was first cab off the rank when it came to being an up and coming star, his stat line was better than Jayson's and he had a clear role, then this year he's fallen behind Jayson (and Gordon) in the pecking order. Think about being in a job where you got hired before someone else and was on a fast track but then they hired someone else younger who leapfrogged you for promotion. You have to have pretty strong self-esteem to not take that personally. Then you have Rozier who wants to prove that he deserves a starting spot and he knows that end of day GMs will look at his stat line when deciding what contract to give him.
Then outside those young guys you have Gordon, coming back from a horrific injury, consciously aware of the fact that this team is essentially the same team as it was last year except that he is the new addition, I'm sure he's feeling like "is this all my fault? I came in and ruined the chemistry and to make things worse my progress has been a lot slower than anyone wants". The team he's now playing in is very different from the team he joined when he was expected to be the 2nd scoring option behind IT. Now there's Jayson who's become the second scoring option and takes 14 shots a game, Morris and Brown 10-11 each, Gordon is actually 6th in FGA with 9.8. You're not going to average 18ppg which everyone expects him to unless he starts to take 5 more shots a game which is 5 less for someone else, unless they increase their scoring average from 111 to 120. At this point for anyone to improve their stat line it's going to come from someone else.
I haven't even talked about Horford, but he's the type of player who doesn't, and has never, cared about his stat line or how many shots he takes, no matter how many people criticize him for "not being a 20-10 player like all the other All Star and max contract players out there". Same with Smart, he doesn't care how many points he makes, because he adds value in ways that Danny appreciated, because Danny probably doesn't use the typical metric that most fans use.
This is an unusual problem. It's an issue of too much talent and the challenge is how to synthesize it into a whole that is greater than the sum of the parts, where each piece making up the whole is individually lesser than if that piece had not been part of the whole. We have at least 7 players (Kyrie, Jayson, Jaylen, Gordon, Terry, Al, Marcus) who could potentially average at least 20ppg if they were the No1 scoring option playing for some also ran team. They're being asked to be lesser than what they can be so that the team as a whole can be greater than it is.