> They don't have to make affordances or adjust for third party users. If they released it with no intention to play nice with the community then all they open themselves up to is criticism and bad press when they inevitably break third party users

I kinda get this but also don't get this. You can always open source something without giving any guarantees to third-party users about stability, feature requests, etc., no?

It would still be useful as just having the possibility to look into the code, and if someone want to build on top of it, then they know the context and have to accept the conditions.