I don't think that it needs changing. I think that it needs publicising so that everyone on the ATC side of things is singing the same song. Maybe it is something for the LCE committees to look into.
If I need someone to still comply with the previous level restriction then I retstate it e.g " Descend FL XXX Cross XXX at FL XXX or below". This works fine and does not impact on RT loading. If you don't believe me, then come and watch the master at work (not)!
It also ensures that any AC types who are waiting for levels based on the level by point are still likely to get what they need to chuck us more traffic.
That this topic has generated such differing opinions is testament to the fact that it is probably quite a safety issue and needs to be highlighted for action of some sort.