While I may not be as invested in the accomplishment as you are, I can appreciate the frustration. I really think that they should have two versions of the raids. They should always have the original version of the raid available, including an iLvl cap (for whatever the max gear was at the time). When they do decide to "nerf" the raid, they should add it as a separate instance option.
For the people that want to experience the content, in it's original form, the devs can give them an achievement with a title, so they can display their accomplishment with pride. For the more casual player, the "nerfed" version can also act as a practice run, for if and when they would like to experience the content themselves.