To clarify, I need some means of adjudicating various things (like whether to hyphenate "nonprofessional"...I just dealt with that today); the NYT has a massive archive that's so easily searchable, so it's very tempting to use the NYT as my basic way to adjudicate things.
Yes, I completely understand. I sometimes consult the NYT, too, though I more often consult the New Yorker when I want to see whether the best punctuators have punctuated something how I have determined it "should" be punctuated.
As to hyphenated word forms, I recommend that you consult dictionaries, too. Regarding nonprofessional/non-professional, there is a British–American difference: the British use the hyphen (O.E.D.); Americans don't (Webster's).
Two other things.
1: I often agree with the logical underpinning of a given NYT decision...for example, I think text looks better and reads better with minimal hyphenation.
2: I definitely do defer to the NYT a bit...they're a fancy newspaper and you have to assume that there are brilliant minds over there thinking away about various things.
Yes, yes. It is fun and often illuminating to speculate as to the logical underpinnings of a punctuational decision made by high-caliber editors.
I have observed a tendency toward minimal hyphenation, even among linguists, who, for example, tend to write "phrase structure rules" rather than "phrase-structure rules." I have long been comfortable with using the latter formulation, however, and see no need to change my ways, even though it is hard to see how anyone could interpret "phrase structure rules" otherwise than as "phrase-structure rules."
The less likely a misinterpretation, the less needed the hyphen. 
The bold is an example where I decided to go against NYT practice:
https://join.substack.com/p/no-room-for-conflict
The US blocks NWFZs because the US wants to maintain nuclear-weapons facilities in the areas where the NWFZs are being proposed.
Good choice. Without the hyphen, not only is it possible to construe "nuclear" as modifying "facilities" rather than "weapons," but it is also possible to misread the sentence, for a split second, as saying that the U.S. wants to maintain nuclear weapons, before one realizes that "nuclear weapons" modifies another word.