It’s a way of creating a sequential control circuit based on a piece of memory holding the outputs and next state for each state.

uOps by microcode

That’s not how it works, only a few overtly complex instructions are implemented in microcode and they are slow, most instructions use a random logic decoder.

You are confusing microcode and micro-ops.

That was a very visible but in the grand scheme of things it was just a small change, it still carried almost the same electric signal and the same Manchester code, the real big change was at gigabit ethernet, it’s pulse-amplitude modulated since.