Related issues flarum/core2240 and flarum/core1006
The number is correct, the problem is actually that you cannot see all of the discussions that are counted.
The odd thing is that the discussions you cannot see should be visible. You have 5 discussions under the Dev tag. I can see them on your profile because I have admin access, but when I go to your profile as Guest I see the same as your screenshot. We might have messed up something during our 1.0 update as it seems the Dev tag is hidden to everyone but admins. I'll check with the team.
