I think your misunderstanding stems from the definition of "decriminalized". Decriminalized does not mean legal. As it is commonly used "speeding everywhere" is

I think your misunderstanding stems from the definition of "decriminalized". Decriminalized does not mean legal. As it is commonly used "speeding everywhere" is, in fact, decriminalized, in that you will not land in prison for it, and the penalty is merely a fine, and maybe some driver's school if you're a repeat offender. This is greatly preferable to the alternative.