I didn't read the other posts in this thread, but wanted to post my feelings on the topic:

I really enjoy running old content while incredibly overgeared. There's just something satisfying about seeing how many groups you can pull and how far you can push it. If the bosses are too easy, you can treat them like any other trash mob - drag the trash from in front of the boss room into the boss and AoE them down together. It's all kinds of fun!

That said, I also really enjoy having a challenge. I don't really want to see the fun SR dungeons go away, but I totally get where the OP is coming from.

What if there was a new roulette, High Level Synced or something, where when you get into a dungeon, everyone is item-level-synced to the minimum ilvl for the dungeon + 10 (or other hardcoded number)? Then, add in the ability for a player queuing for a specific dungeon to choose between the level sync options. Double all non-loot rewards (tomes, gil) for the lowest sync option, or just give a flat bonus at the end. That both preserves the current dungeon setup and provides people who want a challenge with the ability to challenge themselves.

It would make old content interesting again to newer players like me who never got to run dungeons like AK or WP when they were current content.