I’m guessing that it is being construed as racist because the meme depicts a negative scenario while also including a keffiyeh.
If this was done frequently where a keffiyeh were included in memes or jokes with negative scenarios involving people from Arabic countries it could imply a connection between negative things and Arab people. In that case it could reasonably be considered a racist caricature.
I am wondering if there needs to be an established connection between a depiction and a negative aspect first for it to be racist, or does any depiction of a race or culture in a negative scenario inherently make something racist?
After typing that out I am inclined to believe the latter shouldn’t be the case, otherwise essentially any depiction of any negative scenario would be racist.