I actually included that (even used that extremely descriptive word), but deleted it allowing it to be "assumed" under:
3) No funding to operate it

At great risk of splitting hairs, I think the cost of insurance really should be a separate line item, and a potential deal killer. I was involved with a group in the '70s that ran a pair of steam fantrips, and I remember that our insurance premium was almost as much as the fee charged by either of the two railroads to run our trips. I also remember missing a deadhead move, over some rare trackage, because I was hand delivering a copy of our policy to one of the railroad's division offices. (And the deadheads were usually more fun than the actual trips-)

Slightly OT, but the insurance situation has affected other creative endeavors. My wife and I are both musicians; our brass quintet lost our rehearsal space a few years ago, in a church basement, because we didn't have insurance. More recently, a British-style brass band we both play in had to get it's own insurance policy to present a concert on the campus of an Ivy League university. The insurance situation is really getting out of hand.

Been there, done that, WORE OUT the tee shirt, wash the car with it now-

EDM

The short of it is that 759 is just more engine than Steamtown needs, so there is no reason to invest the time and money in a restoration to operable status. There are also other berks out there, some operable, so why duplicate the efforts of others?

She is an impressive engine, and is being decently cared for; she is stored indoors and recently got some new paint in spots as a result of the asbestos abatement program.

759 is doing the best it can for the NPS, that being the role of a valued display piece. Don't underestimate that.