Wait, are you actually asking whether or not it's the player's, or his representative's, fault that they're not agreeing to a contract that is; A) worth the amount that a third body deemed it to be; and B) Guarantees more capital in the first year than any other pick outside of the first overall?
How is that "holding out on principal?" Unless the "principal" is "I don't want to play/live in SD?"
If I'm wrong, I'd be delighted to have an explanation as to why that would be the case.
What "language" is SD including in his contract that the rest of the league doesn't that would be detrimental to Bosa?
Sure, now that he has held out for the entirety of rookie camp, OTAs, training camp, half of the pre-season, and likely more; I'd be inclined to include language that would refuse payment of his lack of service too. Why should he collect funds for services not rendered?