I look at Unity as a Camera. 100 years ago you needed to build your own camera if you wanted to shoot a movie. Now, almost no directors build their own cameras

I look at Unity as a Camera. 100 years ago you needed to build your own camera if you wanted to shoot a movie. Now, almost no directors build their own cameras except for special needs (filming underwater for example). So, do you want to make cameras or do you want to make movies? Translating to games. Do you want to make game engines or do you want to make games? Like the camera example, if you have some special needs maybe you want to make the game engine but for most games, like most movies, just using an off the shelf game engine will be good enough. I agree with you GL is dead. There might be one more version of GL but after that there will be zero pressure to update it because all the top graphics people will be vulkan/metal/dx12 only