I suspect the "clever" people on social media pointing out the different legal situation in different countries of the UK aren't anywhere near as clever as they think. Like other differences, for example minimum alcohol pricing, it will never be tested in court. If it becomes a problem, all that will happen is it will become law in Scotland and Wales after a suitable length of time[*]. If they're against the law, they should argue against it, but unfortunately there is a trend of some in both Scotland and Wales obsessing over being different rather than reasons for being different or not. (And I say that as someone considering standing for councillor for the Welsh National Party, so not from anti-devolution sentiment.)
[*] 3 or so days is usually enough to maintain a veneer of independence.
[*] 3 or so days is usually enough to maintain a veneer of independence.