It's crazy, given that all these devices have something powerful like an esp32, isn't it?
I've done some of my home stuff this way, but I had to program it myself. Tasmota has some features which can be used without a server, but that's just for simple stuff like switches. For whatever reason (simplicity for non tech people?), out of the box products don't work this way.
If you don't have days of spare time, you buy ready made products and set them up in minutes in Home Assistant
Then yes, learning Ansible is a good way to have base OS settings for your systems. I love that it's agentless - works over SSH.
The ugly part is that they keep updating it in a backwards incompatible way. In one version the paramerer is called "file" and in another it's "dest", they pull shit like this and don't provide a tool to update playbooks automatically.
But updating is rather optional.