When Thoreau moved to the woods, he did so because he "wished to live deliberately, to front only the essential facts of life, and see if [he] could not learn what it had to teach, and not, when [he] came to die, discover that [he] had not lived." It is an admirable notion in any industrialized nation, this sense of removing the shackles of the capitalist system and living, in the parlance of the twenty-first century, "off the grid." It was possible (but by no means easy) in Thoreau’s era to avoid the “soulless and debasing” labor he so decried, but in the year 2020 it is much more problematic.
One reason why it was more viable to live as Thoreau did in the 1840s was because land was more readily available at cheap prices than it is today. (And Thoreau didn’t have that obstacle at all; it was a great boon for him that Emerson owned so much land.) Another is that life was, in general, simpler, and there was much less in the way of government regulations to limit a person's freedoms. Also, the mood in pre-civil-war America was still one of limitless expansion and rugged individualism. It was more readily accepted to strike out on one’s own.
Seeing the matter from the twenty-first century, however, we see that, while it is theoretically possible to live as Thoreau did, it would be difficult. For example, although it is possible to secure land in the immense open spaces of the United States, obtaining that land cheaply is virtually impossible. If a would-be Thoreau knew a wealthy land owner then that would be ideal, but it's not a given that a land owner would be as generous as Emerson was or even if such an arrangement would be acceptable and/or legal to local authorities. Even if one was able to obtain the land, there is the meat and cheese question. Growing crops is one thing; harvesting livestock is another. Again, it is possible, but, as mentioned above, there are more regulations today than in Thoreau's time.
The biggest impediment to Thoreau's off-the-grid living is the nature of American capitalism. If there is money to be made, even by a recluse like Thoreau, then there is someone out there to make the money. Today, where would a person moving to the woods find power, water, and the rest of modern-day accoutrements? Power is possibly not needed, but a heat source (most likely from wood) would be, and water is critical, not merely for drinking but for farming. Where would the permits come from to chop down the trees, and who would pay for it? Who owns grazing and water rights?
As challenging as all that is on its own, the greatest difficulty would be how to pay. It is highly unlikely a person today could obtain enough money without engaging in "soulless and debasing" labor. Thoreau may have said that "it is not necessary that a man should earn his living by the sweat of his brow," but the reality in the year 2020 is that people still must earn a living—and they won't earn much of one on a friend's borrowed plot of land, rent-free or otherwise.