I love this idea but it's hopelessly silly.

Newton himself famously talked about standing on the shoulders of giants.

It's not even that the observations that led to Kepler's Laws could not be made - it's that the tools even to express Universal Gravitation or even the Laws of Motion were a thousand years in the future at the time of the ancient Greeks.

Newton could have gotten nowhere without the recent invention of analytic or Cartesian geometry. But analytic geometry in its turn depended on algebra, also "not yet invented".

In fact, ancient Greece didn't even have decimal numbers. Fractions were the only non-integral numbers, and they were expressed geometrically.

You might as well have Isaac the Greek building the first cell phone as discovering Universal Gravitation.

But have some claps for entertaining me, anyway.