You're right, but this argument isn't too far from the "roleplaying" criticism that OP brought up. It can be seen as a more or less charitable manifestation of the same idea, namely that by pretending to be X we start becoming X. On one end this is roleplaying on larping, on the other end this is the Stanford Prison Experiment.
They can have negative effects too (the effects above can be negative depending on context), but I wouldn't discount the influence a decorated room can impose on sentient meat.