I think you are blaming the messenger. Even if the number of market-rate-fee paying transactions declines, those who want to get their transaction confirmed in the next block will need to pay an above market fee, resulting in the market rate fee to increase.
this "messenger" is being advertised all over the forum. whenever someone asks about fee, transaction, why not confirmed,...
this "messenger" is increments fees in big steps instead of small and speeds of the rate of fees going up.
The above will continue until either (a) there is sufficient block space so that miners can include all market rate fee paying transactions, and have space left over for below market rate fees (but above cost rate fees), or (b) the market rate for transaction fees increases to an amount that less users will wish to send transactions (use Bitcoin).
'a' will probably not happen until the max block size is increased, and 'b' is likely bad for Bitcoin over the long run.
a) so far miners are deciding that, and they seem to be pretty happy about the situation.
b) that will happen but is a long way down the road.