The problem with all systems that involve human decision-making is they orient around what they incentivize. Proof-Of-Work encourages making transaction fees as high as possible so that inevitably happens. Whether its a miner conspiracy or just a miner standalone complex, the end result is the same. The technological limitations of proof-of-work make this the most beneficial action they can take for themselves.

Which I guess is my long-winded way of agreeing with you 😁100%

Given the massive environmental and energy-usage impact of POW, I also see 2018 as the year that Proof-Of-Stake takes over and POW is relegated to history.