This comes back to the age-old question: What are "high fees?" Shouldn't we expect fees to rise over time, since they must replace the block subsidy? That was the original design, as I understand it.
Let's imagine a future decades from now, where speculation and block subsidy have much less influence on price. In the long run, shouldn't there be a strong relationship between transaction fees and the actual cost to mine transactions?
Right now, miners are effectively subsidizing that cost through speculation. They're willing to mine transactions for pennies on the dollar because they're in an arms race to mine the block subsidy. Many halvings out, that incentive will disappear. If we want similar or better security, we'll need to pay for it as users -- as fees.