This is a very true issue with Eichel, and it isn't so much that he is a selfish player, but when the team needs to win, he tries to do way too much by himself.
Maybe the biggest issue with this is that he sometimes pulled it off and would win the game for the team on a crazy individual effort, which just reinforced the behavior.
It is like watching all those Penguins - Caps game 7s from a decade or more ago, and watching Ovechkin try to skate through the entire Penguins team time and time again trying to literally will the team to victory without realizing it is a team sport and he needs help.
The year Ovechkin finally realized this, he started passing in must win situations, and the Caps finally beat the Pens.
No clue if Eichel will figure this out, but his passing and vision are extremely elite, so if he ever does, his team will be much better for it.