This is not a coincidence. All in all, seventeen states have had some sort of a proposal like these. I am not saying it is a conspiracy, but it is a series of overlapping acts of malice, including:

• State legislatures proposing legislation to decriminalize hitting protesters with vehicles. Don't think that the "unintentional" clause in some makes it innocent - right wing media immediately justified the Charlottesville murder as "because the driver was scared", and the Charlottesville police initially said the driver "lacked malice"
• Police officers and right-wing figures have made statements about "how to get away with hitting protesters with your car"
• And now we have an actual vehicular attack and murder against innocent protesters by a right-wing extremist

These all go together, and they are about intimidating and punishing protesters. Many of these laws are considered reactions to anti-Trump protests, but in truth, mosts were directed towards Black Lives Matter - not that totalitarian or racist motivations make much of a difference in the effect of legislation designed to limit freedom to protest and legalize harming protesters.