https://www.theverge.com/circuitbreaker/2017/9/22/16332938/nest-thermostat-e-better-than-original

Usually when a company releases a cheaper version of its flagship product, it’s notably worse in some way in order to justify the cheaper price and to keep from cannibalizing the original, more expensive option.

Nest didn’t do that. Instead, the company that made the smart thermostat popular with a $250 device made a new thermostat that is just as good as the original, and knocked $80 off the price (mainly because it won’t be compatible with some higher-end heating and cooling systems).