Yes, the AT command set is used in modern modems. But they didn't choose to use it because of the line speed synchronisation properties. (Edit: and while the A

Yes, the AT command set is used in modern modems. But they didn't choose to use it because of the line speed synchronisation properties. (Edit: and while the AT command set is supported, modern systems tend to use custom command sets in preference. For instance, Qualcomm modems support QMI which provides a binary interface to the modem and modern phones will tend to use that in preference)