As for diminishing returns, are you telling me less than 1 extra strikeout a game causes over half a run less a game? Runs are dramatically down over just the last few years while the approach we are talking about is something over 2 decades in the process. It's a huge reach to think there is some sort of cliff at 7 strikeouts a game.
The simple reasoning is staring everyone in the face. Slugging percentage and batting average are down. Now, if you think the current approach to hitting has effect on slugging and BA, then that makes no sense since slugging is still higher than the 80's and BA is very similar. There simply is no correlation how hard you want to try. Everyone knows the reason for the reduction in runs, and it seems like there is an endless number of people trying to make a name for themselves by trying to point out something less obvious. Occam's razor.
Let's face it. We all know what happened in the 90's and 2000's. Numbers are simply returning to the levels we saw in the 1980's. If numbers were at historical lows I would tend to agree, but they are not. They have just returned to the norm.