While I agree with you, I would like to point out one exception I’ve noticed: veeeeeery occasionally you’ll run into someone with an old junker that either has a broken cruise control or an old, not fully maintained cruise control system.
My old busted up, 70% rusted-out ’99 Ford Ranger that I had bought for like $1000 had the latter problem, where the cruise control would work, but its accuracy sat at around ±1–2 mph or so.