Make it a certification requirement (UL or whatever) for the manufacturer to maintain a gold-level OSS Home Assistant integration, and all those problems would solve themselves in a heartbeat.
Alas, vendors that interface with customers do not sell appliances - they sell "solutions", specifically solutions to the problem of their own making, i.e. them inserting themselves between the buyer and the appliance they're buying.
Alas, vendors that interface with customers do not sell appliances - they sell "solutions", specifically solutions to the problem of their own making, i.e. them inserting themselves between the buyer and the appliance they're buying.