The VC-10 had rear mounted engines so that the entire wing could be fitted with high lift devices (ie full span slats and flaps/ailerons) to provide an amazing short field performance for hot and high operations off short runways on BOAC's African network. Wing mounted engines required gaps in the high lift devices.
The VC-10 had a CLmax of 2.3, but the A320, from the same Weybridge design team achieved CLmax 3.2, albeit with a lower sweep wing, so it isn't obvious that wing mounted engines have worse high lift capability.
Going back to the original question, a couple of other considerations would be:
Susceptibility of T tails to being blanketed by wing wake at high AoA (deep stall problems), and
Great difficulty today to get clearance for the disc burst case where T tails with engines closely mounted opposite each can rapidly turn into a glider with no hydraulics or electrics.