If it was such an advantage everyone would be doing it. Its not. Some players have done it for years and others haven't. Keepers are just suddenly having to follow the rules that they should have been pulled up on for years. All things considered, if you take a normal fast run up and hit the ball hard the keeper won't be able to leave the line in any real way without sacrificing lateral movement. A stuttering run up makes is much harder to change your mind at the last second and place the ball well. Its a trade off. Its harder for the keeper to stay on his line and its harder for the player to generate a lot of power in his shot.
Basically, I don't have any issue with it. Keepers aren't supposed to come off their line. Its a bit like the handball debate. Plenty of players hold their arms behind their back when blocking crosses. If you decide not to then you can't complain if your outstretched arm gives away a penalty.