Back to the title of the thread and the questions posed by Craig.
No sourdough in NY Pizza?
Well, I think we all know and agree to what it means to have sourdough in pizza. I think the problem is that there is no clear definition of NY (Style) Pizza. I say NY Style because if we said NY Pizza, then I think we would infer that it means Pizza made in NY (NYC?) which could mean all kinds of things including Neapolitan.
So, what is NY Pizza?
The forum title describes it as "Also known as Neapolitan-American style. Dough is stretched and/or tossed. Pizza has a bready rim that tapers down to a thin, foldable center."
Beyond that, we are looking at a type of Pizza that has gone through a series of changes over the years, much of it for the worse. It can mean the Coal Style (as Scott describes) / Elite Style (as others describe) which are, among other things, baked at relatively high heat. Or, it can mean the more contemporary, lower quality pizzas that, among other things, are baked at relatively low heat.
So, how does this group of enthusiasts, zealots, newbies and professionals define it? I advocate for a more broad description / definition that reflects the reality of the changes that have occurred (and will occur!). Within that description, we can describe (and promote enthusiastically) the more traditional, excellent type and call it, perhaps, Traditional NY Style Pizza. And, we can describe (and trash) the more contemporary and ubiquitous type.
The broader definition can allow for future evolution (hopefully not more deterioration) of the pizza to allow for SD, hydration levels, flour types, toppings, etc. But, it should still have something important to do with the more broad description, which at this point is "officially" "also known as Neapolitan-American style. Dough is stretched and/or tossed. Pizza has a bready rim that tapers down to a thin, foldable center."
If you buy all for the above, then the answer is Yes. Pizza containing sourdough can be a NY Pizza. It would be a potential evolution, improvement of sub-type. But, it does not represent the "Traditional" (as described above) NY Style Pizza. It cannot since the Traditional is what has been remembered/recorded as historical fact/lore/memory.
I won't get into Says Who? It does not matter until the terms are better defined. And, the undefined term is NY Style Pizza. My proposal of the more broad definition with "sub-types" is, in my opinion, a reflection of reality and history even if we hate some of the pizza. And, it allows room for the future and does not force us to be stuck in one mode (and who exactly is the boss of you if that is the answer?) in this forum.