Not a lawyer; would this likely stand up in court? Obviously I wouldn't risk it were I the dev, but just curious.
It's pathetic that I'll happily recommend my Emporia Vue2 energy monitor to folks running HA --- not because it works out of the box, but because the company is aware of the community integration projects and seems ok with it, even if they don't actually support it. (ESPHome Firmware flash gives you local control --- It's been pretty great!)