So, can we finally mix in some young heavies.

Very solid reasoning.
There was always some of these "reasons" to avoid a fighter in pro boxing, but these days it seems even worse.
Recent to current era it appears it's more about politics, finances, and playing some waiting game than actually making good fights. The HWs seems to be among the worst. SMH

 

Yeah and especially at HW division.
This is in all levels from local club and small hall boxing till world top stage.

Everyone does calculates everything. Not only up comer's teams and managers, promoters. Gatekeepers, formerly well known boxers over the hill, journeymans, even bums calculate everything.
Risk/ Revard, ROI value from this fight.
It is like business.

We of course sometimes see good fights. Mainly when boxer's team and manager, promoter had underestimated his opponent and picked him to fight vs their guy.

Sadly this is what it is and this is business like all businesses.