Honestly it's not that difficult to see why it was called. Defenders are still getting sacks, but plays like these will get called.
The internet can scream all the live long day about "oh what is he supposed to do?" Here's a thought...look at the other defenders. See what Aaron Donald, Von Miller, Khalil Mack, etc etc. are doing. How come they don't get calls like this? Could it be because they don't spear the QBs to the ground?
Ready for them "different opinions".