If my father in law (Mexican descent, 3rd gen) saw that, he would have cut it down and burned both flags immediately.
He retired USArmy (Signal Corps) at SSgt after 23 years. Frail as he is, I wouldn't want to be between him and a treasonous act such as this.
Two thoughts.
The most heinous thing is that the Mexican flag is on top. That is beyond rude and offensive.
However, both flags being flown upside down indicate a country or location in distress.