The trade-off isn't so much about the fact that it's faster so much as it is about player attitude. Take groups for Coil, for example. There are groups for T1 that can, with effort and skill, conquer Cad at i70, and there are groups that demand that you be at i80 before you even try T1.

It's not so bad now since it's just limited to PF requirements, but picture what the super-elitist parties will start doing if everybody's ilvl was immediately examinable. You could queue up for AK, and get booted in the first few minutes because your gear "wasn't good enough for the group", regardless of whether or not this has any factual basis rooted in your actual performance.