There are a few companies that have "closed" systems that are nonetheless extremely easy to integrate into something like Home Assistant, or anything else. Lutr

There are a few companies that have "closed" systems that are nonetheless extremely easy to integrate into something like Home Assistant, or anything else. Lutron, for example, exposes a Telnet port on their (pro) hub that you can connect to and issue plain text commands. Sure, open standards are always better, but I'll take documented local control as a pretty close second.