First, you have to define "conversion therapy" so you know what exactly you are banning. If you mean ANY change-allowing therapy for gender-disturbed or same-sex-attracted clients, then that law has no right to interfere with an individual's personal lifestyle goals.
But if you are listening to Sam Brinton or any of the other activists who say they were "tortured" in therapy, note that he NEVER mentions who his therapist was-- and when asked, has said he "forgot." Visit SamBrintonHoax.com for more information.
Therapists nowadays don't use the aversive techniques the activists describe. If they did, the therapists would have been sued-- and openly named by their former clients. The therapy the activists say is happening, does not exist. So bans are unnecessary.