HIPAA does require it. I don't know of any free video chat services that are HIPAA compliant. As I understand it, HHS has said that during this time, they will be lenient on the matter. But that doesn't mean things like Skype and Zoom are HIPAA compliant or that it's best practice to use them for teletherapy.

I suppose therapists might save money if they fire their receptionist (if they have one) and don't go into their office by saving on gas. The one I see has not laid off her receptionist and she does teletherapy from her office because that's where all the files are. I would not want her bringing those home and the receptionist likely needs them to do billing anyway. The expense of leasing an office also doesn't vanish even if the space isn't being used at the moment. The only plausible expense that could be done away with on a temporary basis is internet - and that's only if there isn't a contract in place and assuming there are no servers on site that must remain accessible remotely.