Core and untouchables are very different and you seem to be confusing the two. Core is a group of 5 or 6 players who consistently make up the team. That doesn’t mean that they are untouchable.
Kings in their prime had a core of 6-7 guys but each one of those players could be had if the right deal was offered that could make us better. Someone like JWill was part of the core but he was traded for an upgrade. Guys like Bobby and Doug and even Bibby were part of the core but if they were to return an upgrade in talent, they sure would have been moved.
Hedo was part of the core but he was traded along with Pollard for Miller.
Core is a group of players that make up The basis of the team. It’s generally 5-7 deep. Those players generally fit well and will stay together for a while but it doesn’t mean that they are untouchables.
There are franchise level players (eg. Webber)
Perennial All-Star level players (eg. Webber)
All-Star level players (eg Peja)
Borderline All-Star level players (eg Mike Bibby)
Important players for the make up of the team
Interchangeable pieces (those that can change year to year)
I always saw someone like Bruce Bowen as part of the core of the great Spurts team but it doesn’t mean that if Spurs need to include him in the trade to get an upgrade that they would not have.
This team has the following:
Potential Franchise Level / Perennial All-Star level players in Fox and Bagley.
Potential All-star level players in Buddy and Giles
Borderline All-Star Level (maybe...maybe Bogi)
Important players for the make up of the team (Bogi and Barnes)
So from my perspective the core is Fox, Bagley, Buddy, Barnes, Giles and Bogi.
That’s really 6 players. Maybe Fox and Bagley are untouchables (if they become true franchise level players). Everyone is else is important but not untouchable. If PHX came to us and said give us Hield for Booker, I am pretty sure we pull the trigger on that move. It doesn’t make Buddy any less important to us going forward.