As the other Anon noted, you get an Anon honest answer, or none :-)
Anon One is exactly correct. Trump is regarded by the rest of the real estate industry as a nasty, borderline dishonest, asshole blowhard whom no one would voluntarily work with, and absolutely no one trusts.
All of the other Anon's points are on the nose:

Trump has very little liquid cash, so he can't write equity checks to play
His "net worth" is laughably small compared to what he claims
His boasting braggadocio leaves everyone else in the dust, which for New York would have been considered previously impossible
He's gone broke multiple times, although that wouldn't necessarily be a problem. So have Eichner, Macklowe and others, but at least they did it with some humility and class
His reputation as a fair-dealer is non-existent. He is known to haggle, cram down and outright cheat his contractors. This is a universal known in NYC.
All of the "name" properties are simply licensed uses of his name, for which he gets fees and a piece of the action. He has virtually nothing at all to do with them, nor does he own them.

So yeah, he's regarded as a joke in NYC real estate circles. But the reason both of us are Anon on this is because, like a nasty drunk, he also has a reputation as a viper. No one wants to publicly cross him, because he plays dirty, has the world's largest megaphone, and has no shame. Cross him at your peril, because his responses tend to be nuclear...and what rational person needs that?