It's a welcome change, but not necessarily noticeable in the bulk of tower dives.
AD scaling on them over doubled from 4 AD/min to 9 AD/min. However, this changes outer turrets from 152 AD - 180 AD at the 7:30 mark, to 152 AD - 215 AD at the 7:30 mark. Outer turrets now scale to 278 AD when the plating falls, but previously scaling stopped at 180 AD at that 7:30 mark. The other towers all got their scalings increased from 4 AD/min to 9 AD/min, but those scalings capped quicker now at 17:00. Even though the old towers scaled late into the 28:00 mark, the new sharp scaling makes the new turrets slightly stronger at its 17:00 cap compared to where it used to be at its 28:00 cap.
To go over that info, early game, the outer turret is going to start to sting slightly more until the 7:30 mark, at which point it will actually start to get potent. At 14:00, outer turret armor falls off, at its peak damage. All other towers should be quite potent at that point, and will only scale another 3 minutes until 17:00. The tower strength on those towers will be stronger at their 17:00 cap than the old ones were at the 28:00 cap, so definitely be wary of tower-diving inner turrets when midgame comes around now.