It’s silly because it shows a very great ignorance of the history of thought.
The basic question of “is the world real?” stretches back a long time.
Its first form was probably: “is the world real or is it a dream?”
Then we started talking, and we asked: “is the world real or is it a story?”
Then we started putting the stories on stage, and Shakespeare said: “All the world’s a stage, and all the men and women merely players, etc.“
Then computers happened, so now we’re like: “is the world real or is it actually a simulation?”
Something else will probably happen eventually, and the basic metaphor will change accordingly.
But the answer is always the same. If you want to look at it that way, then it will appear that way.
If you want to buy into the information provided to you through your senses, then the most plausible explanation is that the “internal”, “subjective”, phenomenal world is a simulation which our brain is making of the “external”, “objective”, noumenal world. And the main reason we doubt this story is because of our fear of death and tendency to wishful thinking — it’s the acceptable, contemporary, “secular” version of the old superstition of an afterlife. And also because, when you push consciousness to its limits, it does kind of feel like you’re zooming out to somewhere else and then being pulled, kicked, or ‘plugged’ back in again.
If you don’t, then the most efficient way to phrase the insight is: the world is really God / Nature / Brahman / the Cosmic Self / Śūnyatā / 理 / 無極, etc., and this perception of separateness that we think of as the world is an illusion.
It is the Universal expressing itself as the Particular. Because the one necessarily implies the other.
That’s about as far as I reckon language and reason can take us.