I'm not sure you should "cheap out" on headphones per se. The really cheap ones are usually horrible, both in terms of sound quality, usability and comfort (well, except for wired Apple ones, allegedly, though they never fit me right). It's just that it makes no sense to go for really expensive ones, unless you're really into audio and love hearing the tiny sound reproduction differences between them, or enjoying the different tech etc. The middle ground of $50-$100 for in-ears and $100-300 for over-ears will often offer you good/great/excellent sound quality and the same usability&comfort as more expensive ones.

Yeah, I've noticed this too. I'm not an audiophile, but I do enjoy quality audio. Everything seems to plateu around the 300$ price point. At that level, the sound is reproduced with as much accuracy as reasonably possible, and the build quality is pretty good. Anything beyond that point is basically added "features" and does not reflect improvement in sound reproduction.

I don't want "Tripple bass rumbler", or "Crisp treble supercharger". I want my headset to reproduce the audio as perfectly as possible, without altering it.

Come to think of it, adjusted for inflation, the Roland headsets I've had for the past 20 years have all been around 300$

Yeah, I'm in pretty much the same agreement. As long as it's tuned well, comfort takes top priority for me. Sometimes though, the right combination of things can cost a bit more.

I can't say I necessarily agree on this one as I really enjoy my nicer headphones, but $300 is probably the price where you hit some serious diminishing returns. It could also be argued that many (most?) of the more expensive headphones have no business being priced like they are.