There is a supreme irony in criticising AT&T for not being a platform while predicting that it will be killed by a company that uses it and similar wholesalers as platforms.

There is a difference between Twilio, a telephony retailer, and AT&T, a telephony retailer an distributor. Twilio and the like may hack you away from the retail arms of the telcos' retail arms, but it does nothing against the distribution businesses. The latter can survive without the former; the inverse does not hold true.