Well, I don’t know what to tell you. For me Vulkan and vulkano are clearly the future, but the only question is at which point does it becomes accepted that games don’t run on old hardware anymore.
It’s a bit similar to the situation with Internet Explore 6 a few years ago. Nobody wanted to make websites compatible with IE6 anymore, but at the same time users continued to use IE6.
I’m personally developing a game with Vulkan because the nature of the game (a simulation with tons of data being updated at each frame) means that people will probably understand that it runs only on Vulkan. And it’s not a lie, since my early versions were using OpenGL and I decided to switch after encountering bugs and poor performances.
But if you want to write a clone of pong, people are going to wonder whey they need to buy a new video card for that.