Here's the original quote:
Right. Otherwise we couldn't have a finite limit of 21 million coins, because there would always need to be some minimum reward for generating. In a few decades when the reward gets too small, the transaction fee will become the main compensation for nodes. I'm sure that in 20 years there will either be very large transaction volume or no volume.
People should really go back and read his old posts here on the forum. They provide a lot of insight into why Bitcoin was designed like it was.
As it turned out, the block size limit Satoshi added is a very important mechanism for generating the fees required to compensate miners. Without some mechanism to disincentivize spam and drive fees up, we would have a tragedy of the commons situation, where everyone takes up block space without paying for it. That can't work where there is a limited supply of coins -- with each halving, miners get less and less subsidy. Eventually, they'll only get transaction fees. We need to incentivize miners to secure the network.
With the full quote satoshi's vision is laser focused. It might now seem obvious but hindsight is 20/20.
Thanks squatter this is exactly the kind of post that deserves to be merited, doing legwork and offering insight as well, if I have any merit left I'll send you some.