I would argue that fossil fuel is not the only determinant
The hard part is that we have become almost dependent on integrated circuits. This goes for any computer device, all control devices in manufacturing, and much more
If civilization collapses, how can we get back the IC fabs going with specialized material?
I wrote about it in a previous comment: 19th century technology vs. mid 20th century.
And expanded a bit on it in information readability and longevity in the digital age.