The UCI has been hypocritical, inconsistent, and mendacious in its claims here.
At the dawn of racing the UCI banned the recumbent Velocar not because it was so much faster (it was), but because the powerful (ahem) upright bicycle lobby demanded it.
The there was the Moulton, which started winning lots of races on its 17" tires in the 1960s. The UCI notionally banned it for nonsensical "safety" reasons, while it was really about small wheels being too fast. The big-wheel bike manufacturers had gotten scared.
Meanwhile, while the UCI was busy banning minor things like beam bikes, disc brakes, and even different rider positions (!), it was perfectly happy to allow huge changes in materials (carbon fiber notably), pedals, and wheels.
And then there's the UCI largely ignoring and wrist-slapping the biggest technological improvement by far: performance enhancing drugs.
So if you don't mind, allow me to be annoyed that the UCI has destroyed the small-wheel and recumbent market in the name of consistency, while being largely complicit in the biggest sports drug scandal in history.