What you believe doesn't really matter.

Plenty of 'ancient' CPUs had microcode.

68K, System 360, Sperry 1100, and even the 'ACE' to name the great grand daddy of them all had microcode.

Technically the 6502 and the 6800/09 did not, they used a dedicated decoder that was closer to a statemachine than microcode, even though both were implemented in hardware.

None of the smaller CPUs had 'loadable' microcode, but plenty of the larger ones did.