I think McArdle is pretty spot on in regards to Woodside's tone-deafness and odd moments of not recalling the stories very clearly. There is indeed a type of libertarianism that comes through in the Little House books, but Woodside does little to show why we should think that this comes from the daughter and not the mother. For instance, Woodside writes:
From the start, there was tension between their approaches. Wilder argued for strict accuracy, while Lane, the seasoned commercial writer, injected made-up dialogue, took out stories about criminals and murder, and—most significantly—recast the stoic, sometimes confused pioneers as optimistic, capable people who achieved success without any government help.Now, this is a really odd complaint, because as McArdle points out the characters talk numerous times about how homesteads are gained by government grant. In By The Shores of Silver Lake, we get an extended sequence (and a return of a character from Little House on the Prairie) dealing with Pa's effort to file a claim down at the government claim office. And in Long Winger, Little Town on the Prairie and Happy Golden Years, Almanzo talks repeatedly about how his homestead claims are a bet with Uncle Sam that he can farm the land.
The Little House books barely mention the obvious, which is that the impoverished Ingallses never could have gone to Dakota Territory without a government grant: Like most pioneers, their livelihoods relied on the federal Homestead Act, which gave settlers 160 acres for the cost of a $14 filing fee—one of the largest acts of federal largesse in US history.
In another case, Woodside takes what's arguably an anecdote which shows the power of community standards and solidarity over market forces, and acts as if it cuts the opposite way. Here's her claim:
The next book, “The Long Winter,” stops for a moment of free-market speechifying almost certainly added by Lane. When a storekeeper tries to overcharge starving neighbors who want to buy the last stock of wheat available, a riot seems imminent until the character based on Wilder’s father, Pa, Charles Ingalls, brings him into line: “This is a free country and every man’s got a right to do as he pleases with his own property....Don’t forget that every one of us is free and independent, Loftus. This winter won’t last forever and maybe you want to go on doing business after it’s over.” It’s an appealing, if perhaps wishful, distillation of the idea that a free market can regulate itself perfectly well. Wilder rarely wrote extended dialogue in her own recollections, the manuscripts show; her daughter most likely invented this long exchange.Now, here's what she leaves out: The wheat was obtained by Almanzo Wilder and Cap Garland taking a near fatal trip to get the wheat from an outlying farmstead. Loftus provides them with the money they take on the expedition. He would have lost his money if they men had died on the trip and never been found. Almanzo and Cap don't charge for their trip, but Loftus tries to charge a big markup on the wheat on the theory that he took the risk and there is no other wheat to buy (except Almanzo's seed wheat which he's keeping secret because he doesn't want to sell it.) There is indeed a near riot, Pa does talk people down, but then Loftus (realizing that he needs to live with these people afterwards) sells the wheat at cost. The incident becomes an example of community solidarity under stress with the young men and the shop keeper both providing free help to the community despite extreme risk.
The issue here, I think, is that Woodside sees the fact that Rose Wilder Lane was a libertarian as a big find, and so she wants to read a conflict in between the mother and daughter's values and imagine that Lane wrote libertarian messages into Wilder's books. What she doesn't seem to imagine as possible (which from the books and from anecdotes I've read about Laura and Almanzo themselves seems to me a pretty realistic idea) is that Lane's libertarianism sprang, to a great extent, from the self-reliant agrarian values of her parents.