It is due to how players are being taught coming up, it has been for awhile and has just recently become the thing in MLB. Pitchers throw as hard as possible, which can be seen in the huge increase in Tommy John surgeries. Pitchers are destroying themselves playing this way. Gone are the large amount of 35+ selective pitchers, pitchers who can't throw at 90+ for long periods of time get moved into relief or disappear into independent leagues.
Batters being only hitting for power is another new thing. Probably this trend started in the late 90s during the steroid era, but now doing so without PEDs for the most part. Baseball got real exciting when everyone was hitting homeruns. No one cares about base stealing or bunts, only geting points on the board. Which makes the extreme shifts mechanic strange since it is something you'd heavily employ against contact hitters. The shift always existed it is just the extreme shifts that are new. It is out of place and that is the only reason it shouldn't be used the way it is.
But just watch out because some up and coming manager is going to put out a team that uses the "old" practices and catch everyone off guard. Might take a while tho.