As a previous Arch user I don't understand what you mean by "best of both worlds"? The point of Arch is to be mutable to a great extent and shipping vanilla packages.
For example, it is quite annoying to have a sane font setup due to Arch shipping vanilla. Fontconfig sucks, it has bad documentation and Arch Wiki examples go only so far. Among the entire distro universe only Fedora has sane configs. So an immutable Arch goes against immutability.
Moreover OSTree requires a server to receive updates regularly, are you going to put the effort to building the OSTree multiple times a day? Why should we trust a single person?
Ostree and immutable distros in general are seeing a renewed interest lately for mostly security reasons but they have been and are still widely used for appliance-type devices.
I could see someone wanting to build an arch based firmware with OTA updates use this as a proof of concept. Yes, they would have to customize it and operate some infra but that does not make it useless.
this one technically doesn't have an ostree server because it would require dedicated infrastructure, but if you decide to either try out images (they're in ghcr) or fork the project and build your own, you can schedule nightly builds (as it's being done now) and use bootc rather than ostree. the problem is that you'd always have to pull a 2GB image rather than incremental updates.
For example, it is quite annoying to have a sane font setup due to Arch shipping vanilla. Fontconfig sucks, it has bad documentation and Arch Wiki examples go only so far. Among the entire distro universe only Fedora has sane configs. So an immutable Arch goes against immutability.
Moreover OSTree requires a server to receive updates regularly, are you going to put the effort to building the OSTree multiple times a day? Why should we trust a single person?
I could see someone wanting to build an arch based firmware with OTA updates use this as a proof of concept. Yes, they would have to customize it and operate some infra but that does not make it useless.