Seems a bit like a "walking simulator". not necessarily a bad moniker - Gone Home was also a "walking simulator" and managed to be one of the best games of the year when it came out in 2013 - but definitely a bit dubious.
For me, I think the thing that will keep me from this game is that I have both read Walden and also read about Thoreau, and know that he was significantly less alone and dependant than he makes himself out to be. The entire enterprise wouldn't have been possible if Emerson hadn't let him stay in his house when the weather sucked, fed him, etc. not to mention the financing.
I can't tell if making a game out of it is appropriate or not because of how fictional so much of Walden is.
I do admire him for his essay, Civil Disobedience, though.