Which just goes back to my original point, if these small titles had been interested making open source games they wouldn’t use Unity.
It doesn’t matter how big the owner is anyways, you don’t own the IP.
So Unity being open sourced wouldn’t matter for a 3rd party trying to port it, and the majority of these small titles that initially willingly built on a closed sourced platform are not going clamoring to port their own games to new platforms decades from now.