While I agree with what you're saying, I say this would be more accurate if it was 30 years.
The problem I see with Bennett is in what I believe is a misguided mission. For some asinine reason there is a mentality that the park needs to increase its visitor numbers. This has been going on for quite a while now and the ridiculous part of it is that the stream has been degrading all this time.
Much of the big push from the early 80's goes back to Sam Welch and Jim Rogers, Welch wanted numbers and Rogers wanted money, but in all fairness the trend started before Rogers. The canoe rental is a great example, nothing to do with fishing or the stream branch.
As far as size goes that is just one more example of trying to increase visitation. People who fish want bigger fish, after all they pay for them and they are hatchery raised. I don't know when the call for a C & R section started, but it 40+ years ago. It's fallen on deaf ears and it will because it endangers the visitation numbers.
The sad part is it ain't gonna change.