This critic really undersold the movie. It is a dark satire about activism. Since people who are involved in activism are really sensitive to any criticism at all, it's no wonder they are trying to dismiss this movie as nothing but a senseless gore-fest. The message of the movie is that activists are naïve at best and corrupt at worst. As for the alleged xenophobia, it's not there. The movie doesn't portray the disconnected natives as villains. Sure, they're cannibals. However, they are just people minding their own business and other people from the outside world are intruding on them. If anything, they come off as more victims than villains.
Even though, this movie is dark, cynical, and gory. It does offer some glimmers of optimism. It must be mentioned that this movie is also really funny. It's not completely a comedy. It does asks you to acknowledge the absurdity and hypocrisy of the activist group and the situations that they get themselves in.
Overall, I really liked it. It's not the best movie of the year. It is a really good horror movie to check out in the upcoming month.
I do want to add one postscript. For the people who are complaining about the "xenophobia" and "racism" of this movie and No Escape, because white people are victim of violence at the hands of people who aren't the same race as them. If I were to follow your logic, I must assume that you also found movies like Fruitvale Station, Selma, and 12 Years a Slave "Xenophobic" and "Racist". After all, those movies feature a race of people who were victims of violence at the hands of people who aren't the same race as them.