The reason noone is really jumping on projects like this is too much liability. Home Assistant is a platform for tinkerers. It’s open source and most importantly, it feels like open source. While very powerful, things are always moved around, the amount of breaking changes is staggering. Depending on your setup you may have to spend a lot of time simply keeping things working. People doing home automation as a hobby can (usually) accept this. But when doing this commercially, this unstable target can quickly become a real support liability.
Typically home automation falls into two broad categories: do it yourself setups and commercial pro setups. The former is very heterogeneous, including anything from cheap crappy cloud based devices from AliExpress over home made or hacked ones, up to rather complex semi-pro DIY setups based on Home Assistant or one of the other open source HA platforms. The latter is based on homogeneous commercial systems like Creston, Loxone, Savant, etc. Those are very stable and mature platforms that come with professional installation, programming and support contracts. They’re also very expensive and don’t allow much DIY tinkering, if any at all.
There’s nothing much inbetween.