Look, imagine you are a scientists in a 3D shooting game, like Quake for example. And you want to figure out the fundamental reality. So in the game, you take game objects and look really close. You find that everything is made up of very small triangles. Then you very carefully slice out a single triangle, and shoots right at its center with some particle like thing from game. You find that something inside the triangle reflect the particle.

You are enthralled! "There is something there still!" you say to yourself.

But there is nothing there! The game engine just figured that the particle would collide with the triangle, and altered its velocity accordingly. But you are too caught up in your assumption that you do more experiments (I think this is what our physicists are doing in our world). But what ever you do, you can only observe the behavior implemented by the game engine, and not the game engine itself, or the computer that is running it....

But you can imagine it. You can imagine an explicitly implemented program and a computer with limited memory that is running it. And if you are allowed to consider it, they can do other experiments. Instead of looking into smaller and smaller things, you can look for other observations that might confirm this. Maybe you can go really far and see if they are not allowed to go beyond some threshold (Ref: The movie "The thirteenth floor").

And would that be pursuing something metaphysical?