Any large influx of foreign tourists at a level that would support new services is fantasy. The airport has been in decline for many years, and what is more relevant is that historically there was never enough support when the figures were around 1m pax to add further growth at the time.
Even more important is that times have changed & the competition has grown stronger, with investment being made to strengthen the position of NCL & LBA.
As for the local population, then a habit has formed whereby alternatives to DTV are more often than not, given favourable consideration. DTV is now operating well below it's critical no. of pax to breakeven suggesting further cuts in overheads. At this late stage throwing investment at transportation links really isn't going to offer any short to medium term support in attracting additional pax. All the while further losses need funding & by whom ?
The future for growth is on a 'regional basis' & this positions have now been occupied by NCL to the North & LBA to the South. Most people I talk to have no qualms at all about travelling to LBA or NCL to take a Loco holiday flight & that together with a catchment area now more attractive than ever to competition says a lot.
As for the Loco's operating in a very difficult & competitive environment, then it makes absolutely no sense to increase risk by placing aircraft at airports which effectively increase their risk profile.