I hear the stop/start all. The. Time by me. Usually at one particular 3 to 2 lane merge (can usually just use the shoulder, against the law but, a regular thing there..
staying on topic.) When the light turns red and you're in a proper lane you're not moving. Vehicles start to move, you hear an engine turn on. No knocks from low oil pressure, either. I listen for that (oil starvation sounds, unhealthy mechanicals, etc.) I never look over to hear the type of vehicle but suspects include a Jeep or Ford. Not 100% on that. Could be anything. May have seen more of those do the stop/start, point is it happens all the time.
People GO from a light, ain't got time to waste, just pray you are not being one of those having a senior moment at a light and taking 3-4 seconds to register the light is green because literally tstaring off into space because ? Driving? What? Where am I? Shouldn't be driving type of people. Happens. So I listen for a "delay" in the engagement. Old school engine, you could conceivably turn the car to Ignition at a long light and turn it back on, if you made sure the time at the light didn't zap your battery (that you'd be able to turn it back on) but you're saving, what, let's say 2 or 3 minutes of idling speed fuel, as mentioned previously maybe in heat where you havethe AC on which works against fuel.. being over 40 now, I don't see myself trying to be playing Let's Turn The Car Off At Lights games.
It has been expressed to me that some systems are so good that they can be at a light, trying to beat the stop/start system, and can't do it. Then some systems may just be sub-par. The 48v systems may be the good ones, maybe they have the engine spinning the millisecond the Mario Andretti even begins to move the pedal down, which is what it would need to be for a driver such as myself, beholden to such ridiculous concepts as "You turn the car on, drive, go where you need to go, park, turn car off." Maybe even leave it running if you want a nice cool or hot car when you get back.
I don't think I would own a car that had this feature, unless I test drove it and could not tell. Then I wouldn't care.
If someone made a point of telling me it did, or if reviews said the stop-start system made driving the car a chore, I would not consider the car.
It sounds like most of the systems are fine, I have no firsthand experience with the newfangled stuff. If it has been left out, that tells me it may have been problematic. Or that EVs are balancing out CAFE so they don't need the confusion. Across the whole model line.
Just a few things there.
Oh and, edit, Scotty Kilmer is basically an entertainment piece. He did help me locate an OPSU once in a visual fashion but other than that.. ugh.