This took a little bit of digging, but I wanted to extract Jefferson's
quote contextually before expounding on the meaning of it or deciding on a particular interpretation.
if a nation expects to be ignorant & free, in a state of civilisation, it expects what never was & never will be. the functionaries of every government have propensities to command at will the liberty & property of their constituents. there is no safe deposit for these but with the people themselves; nor can they be safe with them without information.
So Mrs. Science was faithful to the meaning of the sentence when she chose "A people..."
But even if she posted "People," it's arguable that she would've been even more faithful to spirit of the quote, given Jefferson's pretty consistent belief that free, enlightened individuals make for a free nation and not the other way around. If it is possible to summarize his lifelong core convictions in a sentence, that's probably as close as we'll come.
Her paraphrasing was more faithful to the meaning than most Bible paraphrases for sale at Lifeway. And I think she smart enough not to post something willy nilly. It was something she believed to the core. I can tell looking back (and about a foot away from me).
So Mrs. Science and Jefferson rest on two premises that (I gather) you reject or at least find troublesome: that a population of individuals composes a nation and that they cannot be free while being ignorant.
Upon further review I don't necessarily agree with them either, but I'll write about that and where we may personally disagree tomorrow. When it isn't 3:00AM and I am not looking forward to another fun day of civic duty.
If you find interpretative flaws, please let me know. In the meantime, I'll dream about that next trip to Monticello.