I suspect the SABEN hold was inserted automatically when retrieved from the nav database memory when the ILS procedure was loaded as it is part of the procedure. The crew would likely have been familiar with this ‘gotcha’ but having not flown regularly because of the pandemic, not concentrating on the task in hand and fasting, they missed it. Also pre-pandemic, perhaps getting the shortcut to the ILS was less common as the traffic environment would’ve been busier. OM-C would likely have warned of this trap too (or maybe not in PIA!) but the crew were overconfident and had likely flown this domestic route many times and became complacent.