A reader emailed me this link at the Library of Congress
of an audio file of William Howard Taft in 1908 before he was president in which he was advocating for a postal savings system instead of a deposit insurance system.
It's interesting to note that a postal savings system
was established during Taft's term as president. It lasted until 1967.
According to this government history document, the postal savings systems paid 2% interest. The maximum allowable balance was $2,500 in 1918. This actually was fairly large. Based on this inflation calculator
, that's equivalent to almost $40,000 in today's dollars.