Lexus is the only one doing this to my knowledge. Let them create whatever disclaimer they want whether it means you sign something at the dealer or click an agree everytime you start up your car. There is no defending this decision when you look across the consumer landscape. There's even a site now dedicated to confronting Lexus on this http://www.lexusoverride.com/
I just don't appreciate a car company dictating what my capabilities are while I drive. Some have listed scenarios where it is actually more dangerous forcing people to pull over on the highway with a capable passenger in the seat.
Why not automatically limit speed based on GPS location and how that matches up to the current highway's posted limit? There's no limit to this if you start siding with the lawyers.