You can only share them via private forums hosted by consoles parent companies, like siedev.net, developer.nintendo.com and similar. Direct sharing/selling of middleware/code between companies is usually fully forbidden.
What do you mean?
Specially small developers that would benefit from such free middleware...
The companies hold the gates to millions and millions of potential buyers. Indies want to sell in all of them and there is no other way for them to do so.
In addition, consider that most indies use Unity/UE, which already support the consoles, so vendors couldn't compete on ease of development even if they wanted.
If Godot was overwhelmingly used by indies, then yes, you could be right.