Me too, home assistant integration in google is lackluster to say the least. I think it’s mostly Google’s fault but even just like devices not showing their correct state is pretty annoying…
homeassistant
Home Assistant is open source home automation that puts local control and privacy first. Powered by a worldwide community of tinkerers and DIY enthusiasts. Perfect to run on a Raspberry Pi or a local server. Available for free at home-assistant.io
I'm sure it's Google's fault. Lately they have been more and more siloed with their stuff. All the more reason to use a local hub (even a prebuilt one like Hubitat) and then share the devices with Google Home. That's how I do it with Amazon
I wasn't following it tightly, but would Matter help with cross-compatibility? Or is it only if devices use Google hub as a Matter coordinator directly?
This scripting is a bit different than Matter. Scripting is more "here's what to do with these devices" Matter is more "this is a device"
Matter will absolutely eventually help with interoperability and cross-compatibility, but since it is new, the software stacks are immature, and there isn't enough end hardware. Give it a year or two, and almost everything new will be matter compatible.