remember that are not the miners that make the fee, they could accept even the lowest fee if everyone was using the lowest one and reducing the average, it's up to the peple that decide what fee to use
if for example everyone start now to lower his fee the average would be like the old 10k satoshi per transaction, but instead everyone is rushing to have his/her transaction prioritized and this is increasing the average, miners have no fault here
I think you make a valid point here if everyone decides to use a lower fees then miners have no choice but to accept it, but the problem is as the difficulty of mining increases miners require more hash power and ultimately more money and also after halving they get half the bitcoin that they used to get. So if they are getting low fees low reward and mining cost us high then why would anyone want to mine anymore.