I don't know first-hand, but I'd be prepared to bet there are a non-trivial number of blowhards in right-leaning (therefore, Obama-hating) media who keep saying this must be done, without having any idea of how to do it.
Posing this question to the public is a way of telling those people to put up or shut up.
It will do some good, but probably not as much as you'd think. Media blowhards are quite capable of banging on for years with zero basis in reality. (And then getting elected president.) The best you can hope is that Cruz himself will be shamed into shutting up about it in future, but I wouldn't put money even on that.