My feeling is that most buy the Ecobee because it is one of the few HomeKit compatible thermostats. And that's it.
There is no other compelling reason to go with Ecobee over a Nest, for example. There are zero humans that work at Ecobee to answer phones, respond to emails, or reply to chat support in any reasonable amount of time. Stick with your old thermostat until a more competent company can fill the need in this market.