Make the prohibitions specific to a combination of activities such as driving drunk or high. Someone at home drinking or smoking pot does not pose a danger to the travelling public.
I don’t see that being my logic at all.
I see governments deciding that texting is dangerous based on statistics and then passing laws attaching penalties for doing so.
That seems a perfectly reasonable law to me given the extreme danger and enormous number of miles driven per year.
If a state chooses such a law, then it seems to me that such a law is within their charter.