It’s actually earlier than that, it took standard committees decades to catch up to industry.

The 2.54 cm inch was effectively imposed by Johansson’s gauge blocs back in 1912. The Brits accepted it as the standard in 1930, the American Standards Assoc. in 1933.

The 1950s date you cite is when government finally caught up.

Edit: (Gauge blocks are super cool, btw)