Forgive me, but whenever someone whose most expensive pair of headphones costs $70 says that everything at the extreme high end is the most overrated, that smacks of inexperience and a lack of fundamental understanding of what exactly you're getting with products at that level. Especially because, as far as I know, there are only four headphones at 2k or higher (LCD3, Stax SR007/9, and the Abyss, I'm not counting the Orpheus/Muramasa since they're not even consumer products).
Every audiophile under the sun will readily admit that the law of diminishing returns exists in headphones and becomes more and more apparent the more you spend. Purchasing a luxury item is purchasing a luxury item. No one claims that the relationship between cost and sonic outcome is linear. People buy them because they are the creme de la creme and those with disposable income will spend it to spoil themselves. Simple as that.
It's also entirely possible that you're feeling bitter because you can't afford high end merchandise, and that's something I also understand because I was a poor college student at one point as well who was elated to get a used pair of ATH-A700X. However, you can't call them overrated any more than you can call a giant plasma television or a Lamborghini "overrated".
I don't own anything on that level, although my Pandoras are about $600 more than any of my friends would even think about spending, but I have to say that the purchasing mentality of the Pandoras was wildly different than, say, the M100. I've listened to some higher end merch (HiFiman HE6, Grado PS1000, LCD2, not in the 2k range but close), and obviously it's not "objectively" worth $1000 more than lower end stuff, but that doesn't mean those who have the money aren't justified in their desire to own them.