A piece of advice often given to people is "don't be the smartest person in your team", because then you don't have anyone to learn from.

I think that advice is wrong, because:

1) there are many different skills you can improve and you are probably not the most skilled one in the team in all of them

2) even if you are the most skilled, it doesn't mean you can't learn from less skilled people

3) 'smartest' is a strange criterion, because if there is one thing you can't learn, it's becoming more intelligent

However, if you truly believe there isn't much you can learn in your current work any more, possibly because of the skill levels of your teammates, switching to a different job is probably a good idea.