Guess we'll know who the real Celtic fans are.
The fastest team to reappear in the Finals, from one generation to another, is the Lakers. In 1991 Magic Johnson lost to MJ. The next time the Lakers were in the Finals was in 2000 with Shaq and Kobe. So that's 9 years. No other team went from one Finals to another faster than the Lakers.
There are 2 ways to build a championship team. It's either building through the draft of through free-agency.
The best way to go is building through the draft.
Expecting big name free-agents to sign with Boston in the next few years is not being realistic. Boston is not a city like LA or NY.
So why 10 years?
Lebron will still be playing at a high level in the next 5 years.
Durant will still be playing 10 years from now.
Those two players will be obstacles the Celts have to overcome. If the Celts were to win a championship in the next 10 years, they'd have to do it against Lebron or Durant. And that's without having KG and Pierce anymore.