Here are some reasons not to leap to the conclusion that a structure encountered in the woods = "Bigfoot."
1) The Great Hill Recreation Area, where this was filmed, is a postage-stamp sized park of 203 acres surrounded by suburbia and typical urban sprawl development. See https://www.trails.actonma.gov/great-hill/ size of the park and your map program of choice for a wider view of the area.
2) No one knows how how much range 1 Bigfoot needs to support itself, but an average New York black bear weighing from 160 to 300 lbs. needs 35 lbs of food per day to sustain itself. The average home range for black bears are 1-15 square miles (female) and 8-60 square miles (male) or 640 to 9600 acres for a female black bear. Thus, this park doesn't have the necessary area to support a (presumably) smaller animal. (I gathered this information some time ago from www.wikipedia.com and the links provided therein, and species-specific preservation/hunting websites; the entire chart of 13 large animals and human hunter/gatherers is uploaded somewhere on the forums.)
3) The branch structure looks to be only 20-30 yards of a trail (a blue trail marker is visible from 12:01 to 12:07, right before the camera pans to the left and first shows the branch structure, and again at 13:22. This is consistent with the Great Hill trail map, available at the website above. Even within the park, this is not a remote area.
4) Dead trees that fall between the forks of trees, like the ones that form the main supports on the right (looking at the mouth of the structure) are not that uncommon in nature. Kids (define loosely at 10-16 years old) making secret hideouts from their parents is also not unheard of. Its a great place to hangout and drink beers snuck out of the home frig or to neck (or so I've been told). This also could be a community hangout (again, look at the dense suburbs in the area) where people added to the "shelter" over time.
5) Setting aside the Hockamock swamp area to the southeast, this area of Massachusetts is a void as far as reported encounters go. There are 63 reported encounters in the state between 1861 and 2016 if you add up the reports from 9 different organizations/books/researchers.* Middlesex County, where this park is located, has zero reported encounters. The closest encounter to this park was in the 1960s, over 15 miles away. * Numbers subject to change as more research is done.
Not claiming that this structure is natural. However, nothing supports bypassing more likely explanations (human action) to leap to the more unlikely explanation.
That being said, nothing here should dissuade anyone from spending time in the woods and enjoying the fresh air and off chance that you'll encounter Bigfoot.