I am a noob to home automation but I have a few Kasa light switches that I like. The Kasa switches connect via wifi and Google is able to interact with them. I am also interested in some smartblinds (maybe Smartwings) and I notice they REQUIRE a hub. I understand they are Zigbee over wifi. Why do some devices require a hub and others don’t?
Zigbee doesn’t use Wi-Fi.
Generally you will want to use a hub for your home automation. Most will use z-wave, zigbee and Wi-Fi. Some will also do Matter.
Using a smart home hub, you can have automation routines that tie all devices on various protocols together. The popular smart home hubs are Hubitat and Home Assistant.
No mater what you decide, home automation is not cheap. And, remember, you get what you pay for. Remember that. Lot of Wi-Fi devices require internet, and they communicate a lot with their manufacturers’ servers.