You're right that there is difference in degree. But I don't think that changes the fact that we should already accept that what people post to Instagram are the highlights of their lives and not the drudgery.

It's not a question of acceptance, but rather on the effects it has on people psychologically, whether or not they accept it. Humans don't just operate as rational beings – our brains' perceptions of the world adapt and change based on the things we see and how often we see them. Being aware of this effect is not enough to overcome it, much like being aware of the effects of hard drugs does not prevent you from forming an addiction. It is simply how our minds work. It affects people to varying degrees, but the only way to guarantee avoiding the effect is to avoid such situations in general.

And in the days before budget airlines most people accepted it that an overseas vacation was a bit like that for national lampoon vacations: working stiffs working hard and after years at the job “earning” a vacation. Not jaunts you did while between dead end jobs.