This rule change isn't as radical as some of you are making it out to be.
Defensive holding on an eligible receiver has always been 10 yards and a first down (in the NFL, it's 5 yards and a first down).
The only change now is ANY defensive holding brings the automatic first down into play. Previously, it was only 10 yards. But how often is defensive holding called when it's NOT on an eligible receiver? Pretty infrequently.
So now, if a defensive lineman holds a blocker, for example, it's 10 and a first down. OK. The rule on an eligible receiver doesn't change. It was and still is 10 yards and a first down.
HERE IS WHERE THE CHANGE WILL BE FELT THE MOST, THOUGH:
On punts. Previously, if you're receiving a punt, and you hold the gunner, or any other player, it was a 10 yard penalty. Now, if you do that and it's called, you give the offense a first down. This, IMO, is pretty significant. So the change really won't impact offense vs defense very much. But it will impact special teams more than anything. If it's 4th and 37, and I'm punting, and you hold anyone on my punt team, I get 10 yards AND a first down. That could change some things.