[meheleventyone]

When people say to build a game not an engine they mean “don’t copy the patterns of general-purpose game engines and build something specific to your needs”. There’s not game that doesn’t have bits you can point at as “the engine”. Lots of people get stuck “making the engine” to make their game rather than making the specific engine bits they need as they go.

That said this was the status quo before Unity and whilst it shipped games the asset pipelines and editors in engines like Unity and Unreal are much more productive for the non-programming portion of the team. As well as providing a shared framework that makes it easier to hire and train developers. Not to mention easier porting and so on.

I do think the solution to part of this is an open-source scene editor/flexible tool that has some defined interface that any engine can implement like a language server or similar.