The older the system, the higher the chance it never got a proper security audit, and/or it was built with a lot of implied trust, like most old Internet standards are.
As for 2FA, it is a nice thing to have, but it comes at a significant support cost. People lose their token, people get annoyed by the friction, people can't figure out setup (especially older folks).
As for 2FA, it is a nice thing to have, but it comes at a significant support cost. People lose their token, people get annoyed by the friction, people can't figure out setup (especially older folks).