Your information isn't exactly wrong: it's just incomplete.
The annual limit applies separately to I bonds and EE bonds, so the
total was actually $45k for a while and then it increased to $60k
shortly before the end.

While reading the fine print in the Code of Federal Regulations, I
came upon the useful fact that purchases would not count toward the
annual limits if the bonds are purchased and then redeemed in the same
calendar year. Until pretty late in the game bonds only had to be
held for 6 months. So by buying and selling every 6 months, you
doubled (yet again) the amount you could purchase.

Finally, bonds purchased in the names of two owners would count
only toward the annual limit of the one listed first. If you're
in a family of four you could pretty easily quadruple your
purchases, and still be playing it strictly by the rules.

--ss