I'm still floored by how much power a Tesla uses when in standby functions (+300W!), such as Sentry Mode. A Macbook Pro running at full tilt is 30-40W, and down to maybe 5W when mostly idle.
I know it needs a powerful computer for the many driving functions, but why so much current when it's just sitting there? Is Elon using his fleet of Teslas to mine for Bitcoin?
Though I haven't verified this at idle, just running the coolant pumps is actually pretty significant power draw as well. And they do run for things like Sentry etc. (probably because those compute modules are liquid-cooled). One of my (now apparently silly) notions getting into EVs was they'd be great for stop-and-go traffic because they don't "idle". Boy was I wrong - it'll consume 500W just sitting in traffic in gear (aforementioned pumps and computers, plus daytime running lights). 500W!
For the compute power draw, they probably just weren't designed for "clocking down" like a consumer computer. They were also never designed to be glorified dashcam setups, however they are now used as such. Had that been important original design criteria, things might be different. This is the downsides of adding features in updates vs. at design time -- sometimes the hardware around them isn't optimised for the task. But it sure does generate hype.