It's easy to come up with a list of things that we know that they wouldn't, because we usually know what we know.

Then again, do we? We live in a sea of things we know, there's so many layers we can't even see them.

The simple activity of vacuuming a carpet is actually as complex as tilling a field, even if the consequences of doing it wrong are far less severe. You get the vacuum out of the cupboard, you swivel the little prong that keeps the cord wound up, you find an outlet that you can reach a lot of the room from, you plug the cord into the outlet, type A plugs fit in type B outlets but not vice versa, if there's a large prong it has to be put in a certain way up, some outlets only supply electricity when the associated switch is turned on, the switch may not be located near the outlet, etc. etc.

FWIW, a random historical peasant is about 50% likely to be female.

For your convenience, here's a gender neutral copy of my post:

I know more song lyrics than a random historical peasant.

EDIT: Actually, let me expand on that.

You say propositional knowledge is being gradually supplanted by the procedural. We can see examples of this all over the place. For instance, we used to have to remember a bunch of phone numbers, now we just store them in our phones.

But wait a minute, the random historical peasant doesn't even have a phone number to remember. I at least remember my OWN phone number, that's one more number than he or she does. What's his or her address? Zip code? Social security number? Bank account number? What are the PINs to his or her ATM card, his or her debit card, his or her library card? What are the account names and passwords he or she uses at home, at work, at school, on the various websites that he or she visits? To how many places does he or she know the digits of pi?

If you point to a random thing in his or her environment (Not that there's a lot of things to point at), in how much detail can he or she explain how it works? Does he or she know why ice is lighter than water, why plants are green, how his or her own eyes work?

How many words does he or she know? Does he or she know how to spell them? Does the idea of correct spelling even exist yet? I use a spellchecker, but 99% of the words I type are correctly spelled on the first pass, and I know an awful lot of words.

How many people does he or she at least know the names and faces of? Orders of magnitude less than I do?

I may have more procedural knowledge, but I have a hell of a lot more propositional knowledge too. If you somehow dumped out all the factual knowledge stored in my brain, or the brain of any random modern human, it would be tremendously greater in quantity than that of a random historical peasant. There are people who know more about Pokemon than he or she knows about his or her entire life.