i think, in some ways, who can and cant be a manager is one of those questions still stuck in the 20th century. to be a manager at a football club, you need a few really well defined skills:
- ability to organize your players, in terms of training, fitness and overall preparation
- ability to design a tactical gameplan for each match
- ability to win the respect of your players and keep everyone rowing in the same direction
- ability to co-exist and interact with the rest of the staff at the club, from the academy manager up through the CEO and other decision makers
you can have a young, really intelligent person who hasn't managed for 20 years that has all of those traits. you can also have a guy who has manged for 20 years who has none of those traits.
arteta hasn't managed at any level, but hes a former player, he's played at big clubs, and so i dont think he should be laughed at or excluded from the discussion. the reality is that we don't have any idea what kind of tactical acumen he has, and we don't know if players who are a few years younger than him would respect him. we also have no reason to believe they wouldnt. guardiola managed in the third division in spain for 1 season before he took over at barcelona. he was also only 36 or 37 when he started managing their senior level team.