Arguably any player in the league could be overpaid by another team but they accept being well paid by the team they currently play for due to their own personal reasons.
I could go out and leave the company I currently work and earn more money elsewhere. Like a lot of people I get tapped up and I know I could earn more money elsewhere and most people are in the same situation. But if you are happy in your job and with the prospects then not everyone is infatuated with continually jumping ship for a bit more money. I'm paid a fair and competitive salary in comparison to the market which I know like the back of my hand because I work in recruitment, yet I could be overpaid elsewhere.
If Prescott was offered, as has been widely reported, circa $35 million a year over 5 years with around $110 million guaranteed then that isn't a home town discount in comparison to the market.
If you look at all the quarterbacks that have been signed this year and last, objectively it's a good not amazing offer. Mahomes is a one off and his contract is structured in a completely different manner. Watson is more important to the Texans than Prescott is to the Cowboys due to the poor history of QB's at that franchise and what he brings to the table. He is their offense. Jackson brings a unique skill set to the Ravens and has transformed their offense. It seems as though Prescott is comparing his worth to the Cowboys with those three guys and what they bring to their franchise and not with guys like Tannehill, Wentz, Goff, Cousins or even Russell Wilson. I think that's the disconnect between Prescott and the Cowboys front office. For those on here who view Prescott as important to the Cowboys as Mahomes, Watson or Jackson are to their respective franchises...then that's where I completely disagree with you as well.