I'm not talking governments, etc. I'm talking about tech advances. How long until ag? How long crude then more advanced weaponry? How long until simple machines? How long until engines (steam, coal, etc.), then transportation, telegraphs, phones, computers, etc.?
The scenario is you take a representative swath of 100,000 ( aged 13-50) modern people, set them in an environment identical to earth with no tools, no domesticated animals or crops, etc. It's a fertile world with a temperate climate. Flora and fauna are similar to what they would have been at the time of the neolithic revolution.
I'm guessing they could develop something similar/ close to ours within 1,000 years. Optimistic estimate is closer to 500 years.