Pico Switch
Make your dumb devices smarter.
This is kind of a crappy hack, and it was made out of spite, but it works.
The dumb idea
There are a lot of "dumb" and "stupid" devices. A "dumb" device is one that may not have connection to the internet. A "stupid" device is one that is connected to the internet, but forces you to use a phone app for inexplicable reasons.
Many of the thing associated with these "dumb" or "stupid" devices have cheap remote controls. Even better, they often have cheaper replacement remote controls that you can get at hardware stores for far cheaper than the "official" ones.
So let's say you have a "stupid" device like a garage door made by a Major Manufacturer like MyQ that now insists that everyone use their phone app instead of a proper web app or API. Well, what someone could do would be to pop on down to the local hardware store and by a cheap Garage Door remote for $15, and a Pico W or an ESP32 for $12 or so. Grab the trusty soldering iron and run a couple of leads from the switch on the remote to a GPIO and GND connector on the thumb board, then run this script using CircuitPython 8
Since the thumb board isn't supplying power to the remotes, you can even wire up a bunch of different remotes to the same thumb board and control a bunch of different devices.
Installation
Once you've got CircuitPython installed on the device, you should be able to just copy the contents of thumbboard to your thumbboard, change the values of settings.toml and switches.json to be less made-up and be good to go.
You might want to verify that the files in /lib are correct, but you kinda have to dig through the various Bundles particularly the Community Bundle. I included them here because I want to be nice.
Connecting to HomeAssistant
The next bit would be to run MQTT to act as a message server between HomeAssistant and the thumb board.
This is actually pretty easy. Once you've enabled MQTT, you can go under
Settings > Automations & scenes > Scripts and click the ( + ADD SCRIPT ) button.
You can "Create a new script from scratch" if you like, give it a name and [ + ADD ACTION ] > Call Service
The service should be mqtt.publish and then
Topic: pico/switch
☑ Payload: whatever your switch controls, e.g. garage
☑ QoS: 0
And then hit ( 🖬 SAVE SCRIPT )
You can then create a button on the Overview that calls a Tap Action with the action set to call-service with service set to script.your script name here