It isn’t just a Shyatt/Edwards thing:
https://www.espn.com/nba/story/_/id/14505051/transition-defense-left-offensive-rebounds-cutting-room-floor
In the age of advanced analytics, the trend has been that, statistically, the benefits transition defense trump the benefits of offensive rebounds.
I’m sure that differs from team to team. If I had to guess, I’d guess that if we crashed boards with our not-so-bully personnel, we wouldn’t come up with many anyway and would end up in a bad spot defensively more often than not.
With Shyatt’s teams, the offensive rebounding would probably have had more success than this squad, but he still emphasized getting back.