To unravel the mystery of Leibniz's views, look at his contributions to calculus. He was a mastermind of systems and how they related to one another. Calculus is after all the science of rates of change and systems. So imagine a mind that could invent such a thing as calculus applying those abilities to the timeless, infinite problems of philosophy.
Firstly, it's worth noting that even though Leibniz wrote some bizarre, seemingly untenable philosophy, he also gave us the entire language of calculus and people have been citing him as an authority in maths and sciences for hundreds of years. But as a philosopher, Leibniz is either attempting to articulate something that resists human language, or else he is being reckless and silly. For the first years after his life, that's how much of his writings were treated, but then serious students began to notice that in a strange, indefensible way, maybe Leibniz's metaphysics were correct. If that's the case, then Leibniz would be like a prophet, because his philosophy is deeply religious and deeply transcendental.
In fact, it might be this feature about his worldview that kept him from having mainstream appeal, because not everyone in Western philosophy treasures eastern mysticism. Ironically, though, Leibniz gave us calculus. He didn't give us yoga or something, he gave us the central pivot point of all Western math and science, and yet, his philosophy is often rejected.
So what would accepting his arguments mean? Well for one, it would mean leaving materialism behind for a higher scientific spiritualism. Another implication of his philosophy would be that the universe is watching us. Another possible implication could be that his philosophical works are attempts to put into language his prophetic insights into the future of sciences.
Let's finish by analyzing this last idea, that the monadology is inherently a prophecy for modern string theory. The short answer is no, Leibniz's ideas don't line up cleanly with our current understandings of the world. But don't reject it so quickly, because the Monad idea does indicate the type of bizarreness that we have discovered to be true about the universe. The Monadology can be seen as a prophecy for our discoveries that particles behave differently when we observe them, and that our universe is polydimensional, indicating a strange metaphysical reality that Leibniz articulated hundreds of years before we ever proved it.
In other words, Leibniz is a genius, and even when he's wrong, it's worth analyzing why his mind makes the kinds of conclusions it does, because no one human has been able to speak so clearly about the nature of reality since the Greeks. Leibniz had a deep familiarity with nature that drove his math and philosophies both, so his ideas should be treated almost like religious scripture instead of academic literature, since he created them to be interpreted.
