Mathematics Stack Exchange as an indicator for academic career I'm due to start my PhD in Pure Mathematics next month, fully funded by a scholarship, at an average university, I'll be specialising in combinatorial group theory, and I have a strong First in Mathematics from a Russell group university. My goal is to become an academic.

This is my Mathematics Stack Exchange (MSE) profile. I've been an active user since 2013, visiting pretty much daily, but my reputation is currently just 5,760 and I haven't used MathOverflow at all (as the questions there every time I visit, which isn't that often, are beyond me). This seems quite low. Should this worry me?

To what extent is MSE reputation an indication of potential in academia?
The only thing that a high MSE or MO reputation indicates is that a person spends too much time on the internet (and I say that as someone with a reasonably high reputation on MO).  I don't think you should take it seriously as a data point on how successful you are likely to be.

On a related note, it also doesn't play any role in things like hiring decisions.  At all the places I've worked, someone would be ridiculed if they brought up MO or MSE reputation at a hiring meeting.

It's just recreation.