A large factor of pilotless aircraft is the cost of the aircraft and the reliability of the systems in the aircraft - the cost plummets and the reliability increases
All of the current design and systems are done because there is a pilot , the control loops all have to go to a cockpit , all information has to go to the cockpit and be presented to a human - this adds much complexity and cost ,complexity reduces reliability.....
Think...
there is no cockpit , there are no instruments , there are no throttles , no windscreen, no W/S heating no seat ,no circuit breaker panels ,no dv windows, escape ropes , no flight directors, autopilots , no control column , no flap levers,gear levers trim wheels , no crew oxygen , ipads , manuals , life jackets , no cockpit heating or ventilation , no radios , no radar displays , no wire looms to the cockpit , no armoured cockpit door , no .......you get the picture
systems simplify because you remove the human , he/she is not there to push buttons or look at lights or make choices and actions right or wrong based on information given them by the aircraft.
It becomes a design delight and cheap as chips to do , the aircraft never gets fatigued and can operate 24/7 to exactly the same standard .
now tech develops along different lines , maybe laser guidance , maybe new trim systems or flying controls that automation can control but humans cant , maybe ground taxi systems that avoid collisions ...who knows , but it will be cheaper and ultimately safer .
no hotels,no sims ,no licences,no crew room, no crew transport ,no sickies, no rostering arguments ,no one driving to work , just 1 bloke in ops -lol