Remind me why one needs a thermostat connected to the web? The older, less sexy versions seem to work just fine and are not prone needless bugs.
The actual driver for this is that a good quality programmeable thermostat is a pain to set up, and an equal pain to tweak or optimise. If you're happy with a manually adjusted stat, then you don't have this problem, and if you're happy with a single temperature stat, then again there's no problem
But if you want different temperatures at different times of day (for either comfort, cost or eco reasons), then although programmeable stats have been available for decades, the user interfaces are grimmer than death (well, maybe not quite). Take the Eberle unit on my wall, works a treat and has done for twenty years. But setting up system time, day, four time zones for seven days a week with different household routines on some days....its a pig. The vast majority of digital stats seem to have crap, counter-intuitive four button interfaces designed by the same mongs that design digital alarm clock user interfaces, or multi-storey car parks.
So, in theory, automating the process, using modern understanding of UI, and having learning algorithms makes incredible sense. The unfortunate thing is that the potential has been put at risk by over-ambitious concepts (like smartphone control, and control over internet), an excess of suspect quality software, a lack of attention to security and testing, and a complete disregard for privacy and reliability.
The perfect solution never involved wifi, internet or smartphones, but would still have had a decent UI, touch panel interface, learning algorithms. It would be an appliance, pure and simple, but a good one. By proper testing and conservative specification there would never then be a need for risky software updates, and no problems of security or privacy. Somebody probably already makes this, but the masses are flocking to buy the latest shiney, web-enabled Googley-Appley tat, and any product designer wanting to do the decent thing will be told by the PHB and the marketing department that they have to have app control, wi-fi and internet....