Buy home automation products with local control and no internet communications at all. Ideally with an open protocol, and open source control software.

Same protection against vendor death/depreciation/etc, and on top of that your data is more secure, the system survives internet outages, and you don't have to mess with the immense complexity blockchain adds.

Remote access, if you even need it, can be done through a thousand other methods (direct IP address, tunneling proxy, VPN, etc etc).