You’re absolutely right on that count. If you switch fast enough, everything has a capacitance. That’s why with CMOS designs once you go above a few kHz you start worrying about fan out.
It’s also why, once the ceiling is reached, everything starts using modulation tricks previously used in RF. Ethernet started with 1GbE, USB with 3.0, DSL did it from the start, with PCIe even gamers have probably seen eye diagrams in riser tests, and coax is the very definition of pushing RF over a wire.
That’s definitely wrong. You should follow danielle’s mastodon, she’s working on elementary all the time.