As much as I'd like to see Toronto happen, if I was being on the decision panel for that, the old Bell labs building would be mighty tempting for completely selfish reasons.
I think the "no mass transit" problem isn't really a real problem; most American cities don't have mass transit that is good enough for people visiting from another office to use. I've tried visiting Mountain View with and without renting a car, and it's technically possible, but I gave up on not. Buses are perfectly cromulent forms of mass transit, but tend to be too scary for visitors to use (buses can go anywhere, and it is very confusing/stressful to try to figure out if you are at the right stop and if the bus that just stopped is the right bus, when you are unfamiliar with the system).
I can see the objection to not being a hub airport from both ends. As a normal traveler, SWF is great: easy to get to, park, and navigate, not too expensive, and pretty much anywhere I'm going is one connection away.
From the perspective of a company, yeah, I can see it being a bigger negative. The VPs may not personally want to take non-direct flights, the costs might be more noticeable, and if your destinations are also second-tier airports, you're now talking probably two connections. Especially for what's supposed to be their #2 office, a hub airport may just be a hard constraint.
The upper Hudson Valley probably is too far from New York to really mooch off of its infrastructure, but the lower Hudson Valley (Peekskill, Croton Harmon) probably isn't; however, not coincidentally, you've got a lot more empty office parks in the upper HV cities you mentioned.