Apparently most air taxi missions are less than 1000nm and involve carrying the pilot, a wealthy individual and said wealthy individual's accountant/lawyer. I don't think the TBM's load hauling capacity or range would be necessary for most trips.
I've read this too (w.r.t. the US air-taxi market) but if you offer an air taxi operation you can't restrict it in advance to the head of some Russian mafia and his bodyguard. You just might get a handful of fat blokes and their golfing gear. And fat Americans are even bigger than fat Brits or Germans...
This is one problem which piston twin (e.g. Seneca) charter operators (who also rent the plane out) over here have; they have to make sure any renter returns the plane with nearly empty tanks.... occassionally this gets cut rather too close. But hey, they have an AOC so nuffing can go wrong.
And a few fat Americans and golf gear won't go in an Eclipse, well not for 1000nm in the upper airways.
TBH I don't know how this will be reconciled. I am sure the Eclipse will make a great 2/3-person jet for serious travel all over Europe, and that's what most owner-pilots want, but air taxi??