There are a couple of key points to consider: First, If miners can change Bitcoin to increase the fees is Bitcoin really decentralized? Second, and most importantly, do these increased fees help bitcoin to be a better form of digital cash?
You are right, miners and third parties like centralized exchanges are the ones making profit from the fee that a sender pays. As different centralized exchanges have different rates according to there structure. They all are making different profits from the extra fee that sender pays. Well, at the end all the fee goes into the hands of miners.
I was reading a thread on another forum where they says, miner made more than 40+ BTC in a block I think it was the halving block. And they made 40+ BTC in fee only. I mean the blockreward at that time was still 6.25 I suppose, and miners made 40+ BTC that gives me different thoughts like I thought miner might leave this passion as there will be less profit but nah with an increment in the fee more miners will join. And speaking of runes, I still think its on purpose and many things will be in front of our eyes soon on purpose just to increase the price of fee.