Defensively, Bo is going to continue to regress at shortstop and will need to move off the position.
Secondly, his offensive skills seem like they could deteriorate in a hurry as he ages. Relies heavily on putting the ball in play and doesn't walk enough. He needs to hit .290-300 in order to have an OBP around .340 and his max is likely 20-25 HR's per season. Feels like a Javier Baez contract waiting to happen, worst case scenario.
With an emphasis placed on team defense, the Jays might not even be interested in bringing back Bo. They might prefer a glove-first shortstop, or plan on moving Gimenez over. We'll see what happens. For sure the front office has an idea of what direction they want to go in. As well, the Jays will need to sign at least two arms this offseason (preferably an ace and a solid mid-rotation arm), which will cost money.
As from a fan/PR perspective, Bo is a fan favourite and definitely is a marketable player. When people think of this Jays team, they think of Vladdy and Bo. He's definitely cemented himself as one of the core players and faces of the organization. So the Jays & Rogers will have to weigh in that impact of either letting him walk or re-signing him to an extension.
What will the market be like for Bo? Not sure. Many of the big spending teams are set at shortstop (Yankees, Red Sox, Cubs, Mets, Giants, Phillies, Padres, Dodgers). Off the top of my head, the only two teams that might be interested in Bo could either be the Braves or Mariners, and that's if they want to spend that kind of money for him.