You might not understand what homebrew in a software sense is then full stop. Homebrew in software just means not commercially made/backed.
GNU/Linux and plenty of other open source projects that power your modern life and the internet started the same way.
Opening the comments section of stories like this is always a real eye opener for the type of people lemmy has attracted kinda sad.
Couldn’t do it to myself, there is a reason MVNOS are cheaper they get deprioritised access to the network and the big one they collect all your data for selling.
That’s the definition for games consoles specifically, I know you pulled it from wiki :)
Every computer that comes preinstalled with windows also falls under your definition though as does any Mac.
Linux was also developed for or spurned by a system that was proprietary and only for educational purposes MINIX.