I see my e-mail when I click my profile, can other people logged in see my e-mail or is that private by default?
It's only visible to you and the moderators. Same goes for your IP address.
Your email is only visible if a moderator uses the backend of the system and certainly not seen from the forum front end.
Your IP is available to moderators in both the front and back end of the system and we have specific needs for that.
Arduino takes its privacy statements and its security very seriously.
Bob.