I checked my Note 5 and as expected I don’t see an option for VoLTE. Verizon and Sprint can benefit from Voice Over LTE mostly because can do calls and surf internet at the same time as those ATT users had been forever. I am sure call quality matters but my Galaxy Note 5 is one of top 10 devices for voice quality so that does not motivate me to get VoLTE. I would consider it Progress when it happens and as all Progress those whom are backward and make their prosperity or survival in backwardness would fight what Progress brings that obsoletes them.
Galaxy Note 7 is already years ahead of any Apple device and must be attacked day and night to stop devaluing backwardness. Things need to stay the same for at least one year until next year when new backward super phone aka iPhone gets released and no new technology pushed out until Apple acknowlwdges it’s invention coinciding with arrival of a new iPhone or attacked your product and company will get.