Well, the car isn't always throttled in that example, only in some limited occasions when you would be on a congested road, and only if driven the car for thousands of miles already, and even then only if you are not under a contract with the rental agency at that point. They are basically saying that even though we have granted you the right of being able to use our unlimited plan that we haven't offered for years now, there are some restrictions that it comes with now in exchange for the right to use that no longer existing plan that you can use simply because we've allowed you to. Or you can definitely change to what is currently being offered and go with that without those restrictions.
But if driving the car is not really useable at 20mph or less, why offer the plan. Plans always come and go and with being with VZW for 15 years, I've seen my fair share.
VZW should make good and offer up a comparable plan at an equal price. Not make me switch for less and pay more. They could abolish the plan unilaterally, but I think they would get a raised eyebrow or two from dome regulatory agencies.
Anyway that is my opinion, and I disagree with your stance. Regardless of how I feel they are going ahead with it. We'll see how it plays out.