In 2001, I felt Bledsoe was more talented, but Brady was the far better fit for the Patriots' offense and they needed to trade Bledsoe.
The problem with Bledsoe wasn't talent. It was that he was a product of a QB system that became obsolete in the 21st century. He was a seven step drop QB with a cannon arm. In the 21st century, that leads to about 5-7 sacks a game. In the modern NFL, QBs have to get rid of the ball quickly unless they are a mobile QB or a QB who can move around the pocket. And even back when QBs like Bledsoe flourished in the 80s and 90s, they still wouldn't work in the Erhardt-Perkins system which the Patriots' offense was based off of in 2001.
I have no idea if Belichick thought Brady was clearly more talented than Bledsoe. Neither do you. We do know he didn't think Bledsoe was more suited for the Patriots' system or going up against the defenses of the time.
But if Marino (who is arguably the best seven step drop QB in NFL history) was in his prime and playing in the 21st century, he probably would have been nothing more than an above average QB if that. The NFL had already passed Bledsoe by by 2001. You don't see any seven step drop QBs in the NFL for a reason.
I am not recreating history. I am just looking at situation the way it was. Bledsoe was just not a fit for the Patriots' offense. It had nothing to do with how talent he or Brady had, it was just Bledsoe was bad match. It would be like if Belichick had Troy Brown running deep routes all game or Ted Johnson playing mostly in coverage.