As someone who was poor and now is not poor, that’s bullshit. I was for sure envious of well-off folks around me. Now I absolutely don’t take it for granted.
The character is the only one with sunken cheeks; and thinness is a stereotype of poverty; the walls reveal bricks in places, so the house is not properly maintained, another stereotype; the tablecloth follows a fashion, the Vichy, dating from the 30s and associated with the elderly, and the fact of using old and/or outdated clothes/furniture/decor is yet another stereotype. For an image that has few details, that's a lot.
I think its a valid example though. Sometimes poor people can save up to go out once and splurge on lobster. People tend to post the highlights of their lives on social media. I think the point here is to not buy into it so much