As stated it's become a huge issue which is destroying the game.
Why you may ask.Well it's haveing negative effects on new players especially.They aren't actually learning a lot of mechanics in dungeons,trials raids.
Because why should they right?They can do all the level 50 trials unsynced so they can get free carries with people in level 60 gear.
And look at how easy the crystal tower dungeons are now?The way the game syncs ilvl it means you have a full 24 man raid with maximum stats from lvl 50.It allows people to skip mechanics and ignore adds.

The ilvl syncing system needs a complete overhaul.It just makes everyone overpowered