To be fair, you can still buy traditional building/home automation products. If you go through the list of vendors on the KNX website you see that pretty much e

To be fair, you can still buy traditional building/home automation products. If you go through the list of vendors on the KNX website you see that pretty much every hip IoT device has a standards-based equivalent from those traditional vendors. Learning thermostats, IP-based video doorbells, smart lights, etc... The difference is one of market strategy. The IoT devices are deliberately low-threshold purchases (cheap, easy to install) because they want to build a customer relationship that leads to extra sales. Nest cam, ring subscription, etc... Traditional home automation products instead are targeted towards a one-time sale of a larger system, so they focus more on ability to design the system how you want, with more standards support and more ability to integrate with other products, but also a much higher purchase threshold and a much more involved installation process. In the end, you have to choose what you want. Do you want a single gadget or do you want a whole smart home system?