That's the static resistance, but when it's switching there is current to charge/discharge the gate. Don't forget leakage currents too, which are quite high in modern CPUs --- they consume ~100A at ~1V when in active use.

Sure, but that is amortized over billions of transistors. If you had billions of vacuum tubes the current draw would be vastly higher.

Transistors in TTL logic use mA of input current because they're bipolar, not FET transistors.

In classic TTL the input currents are also very asymmetric, e.g. for a high level you mustn't draw more than a few dozen µA out of an input, for a low level you have to draw something like 1.5 mA or so.

This is different from current-steering based logic (all kinds of ECL, including CML/SCL) were the current in the circuit stays the same, but only takes a different path depending on state. Supply current is largely independent of circuit state with these.

CMOS didn't exist when the first transistorized computers were made.

Ah, right. I thought the OP was referring to modern CPUs.