There's been plenty of shenanigans involving people swapping out gear to a lower ilvl than what would normally be expected for an instance in the past, but when it comes to tanks (especially those doing this in pub groups) it brings an entirely new risk as a tank will suddenly become a lot squishier than a healer was expecting them to be.

What I'd like SE to do to fix this is do a check once combat starts for any players that are below the ilvl of the instance. If a player is below the ilvl of the instance, they are immediately booted from the instance with a one hour instance lockout.