It is 2015 and 90% of large enterprise have moved off IE 6 or use another browser like Firefox esr in their builds.
Did you know modern IE has compatibility mode! No really most incompetent admins use it now for adding IE 7 sites and later to the intranet zone. This means they can upgrade and emulation runs for older sites.
Banning IE 8 is almost there as you can remind them to install Firefox or Chrome which most should also have. Getting close indeed. It is not 2005 anymore where people have no other browsers