I understand deprecating self-installed Supervisor configurations — as a custom container designed for HAOS, I imagine it requires substantial effort to support elsewhere.
But deprecating “Core” installations sounds to me like a mistake. Ignoring the philosophical incongruity of a Python app that is unsupported running outside a container, consider that Core is the only way to run HA natively on macOS (and Windows, sigh) without a hypervisor (VM) layer since Docker Desktop uses underlying VMs. Not everyone can, or wants to, run VMs on their Mac — or figure out how to install semi-functional Asahi Linux — and it would be a shame to demote this alternative just because it is not popular. As M1 Mac minis continue dropping in price they could be ideal HA machines, but HAOS is not (and may never be) an option, and Docker Desktop on macOS continues to be kind of a mess (hence the existence of Colima), and neither are even mentioned anywhere in the official documentation.
Core install, in particular via Homebrew pipx, is really easy to maintain and doesn’t require a Unix degree. (Conversely, the official documentation for installing Core on macOS doesn’t even work on macOS, which perhaps speaks to the existing level of support).