invent.kde.org is now at GitLab. However, in contrary to GitLab, the KDE identity does not support 2 factor authentication via hardware. I can login to GitLab using e.g. the open-source Solo key. Since most of the major developer platforms are offering webauthn like FIDO2, kde.org should to. At the moment KDE is not even listed here: https://www.dongleauth.info/#developer
A replacement for kde identity is planned. See https://phabricator.kde.org/T8449 one of the requirement of the new system will be the support for 2fa. If you like to help with this task, feel free to reach to me in https://phabricator.kde.org/T8449 or per email carl at carlschwan [do] eu.