Mine have already, and I assumed it was becoming ubiquitous already.

I'm frustrated with it because I get multiple texts, multiple emails, and multiple voice calls & voice messages for every appointment I make. I want maybe one text reminder the day before or a couple of hours before and no more, just in case I forgot to set my own reminder. But usually I do have it in my calendar reminding me anyway, just two more notifications on top of the 10 the doc/dentist sends me... :P

Note that an individual has the right under the Privacy Rule to request and have a covered health care provider communicate with him or her by alternative means or at alternative locations, if reasonable. See 45 C.F.R. § 164.522(b). For example, a health care provider should accommodate an individual’s request to receive appointment reminders via e-mail, rather than on a postcard, if e-mail is a reasonable, alternative means for that provider to communicate with the patient. By the same token, however, if the use of unencrypted e-mail is unacceptable to a patient who requests confidential communications, other means of communicating with the patient, such as by more secure electronic methods, or by mail or telephone, should be offered and accommodated.

Patients may initiate communications with a provider using e-mail. If this situation occurs, the health care provider can assume (unless the patient has explicitly stated otherwise) that e-mail communications are acceptable to the individual. If the provider feels the patient may not be aware of the possible risks of using unencrypted e-mail, or has concerns about potential liability, the provider can alert the patient of those risks, and let the patient decide whether to continue e-mail communications.

https://www.hhs.gov/hipaa/for-professionals/faq/570/does-hip...

This is why fax is still so common in medicine and law (in law there’s also a belief that a fax confirmation says it’s been delivered, if not read, while email is considered less reliable / more easily deniable.