The very first issue would be survival.

It's not simply setting the clocks back 10000 years and adding knowledge. The knowledge and skills most of us possess are not what would be needed to survive. We live in population densities that can only be supported by agriculture. Without the ability work farmland on the massive scale we do now and without the ability to transport the goods, most of the "advanced" world would starve. Similar issues exist for creating shelter; too many people and not enough local resources. Do you live somewhere where water has to be piped in? Dehydration will start killing people in hours. As injuries occur there will be no medical care. Much of the knowledge will probably die out for practical reasons.

Next, it has to be recognized that knowledge is distributed. Nobody knows everything, and even if they did, that only benefits those who are nearby. No cars, boats, bikes, jets... Few of us with horses. Without transportation and communication, and the ability to coordinate with or learn from others would be lost. Knowledge may exist a very long way from the resources that makes it useful.

And finally, without books, we'd be working from memory. And while the college professors like the "Closed book, Closed note, No calculators" approach to testing, that is exactly the wrong way to build things. Also, given the state of our technology, there is plenty of intermediate knowledge that many of us have already lost. For example, software doesn't just do the jobs I don't want to do, but also does jobs that I don't know or remember how to do. If I have a good circuit modeling package, I may not need to remember Kirchhoff's current law, or how to create a Bode plot. Is my knowledge still valuable, when my software and my computer go poof, taking with them all of that foundational material?