I cant answer that,
Personally i believe HACS should be a core integration, and all other integrations classed as custom and are added using HACS mechanism as and when needed
That way if they are abandoned by the maintainer or is broken based on the current HA version then you install and use at your own risk and the maintainer of that integration gets all the flak and not HA
This then removes the huge burden placed on the HA team to try and make sure every current core integration still works each month. The onus then moves to the maintainer and users of those integration to test