I think you're missing that most IoT products are designed to be put into products sold at scale. There are exceptions like devkits and hobbyist products but ge

I think you're missing that most IoT products are designed to be put into products sold at scale. There are exceptions like devkits and hobbyist products but generally, the expectation is that everyone interested in IoT hardware is developing a hardware product and needs little more than a convenient interface to prototype and evaluate with before buying millions of chips to send to a PCB fab. In cases like this, you want to pay only for what you need, monetarily but also thermally and in PCB real estate. You can't afford to have a bunch of random unnecessary sensors on board. That's why you don't see some smartphone-esque everything-included devkit. If you want a nice composable ecosystem to built things with, I'd look at Arduino and Raspberry Pi. They have a variety of "hats", which are extensions that you can use to interface with things, like a GSM modem or a sensor suite. I'd also look at the TinkerForge ecosystem, which has a dizzying array of high-quality, well-integrated, pluggable blocks that you can use to construct various things. It is expensive however.