I did say this was to look like you came from an NYC publishing house! Other publishing cultures are different, yeah, and I don't know as much about them. (And I don't particularly like that current house style - a lot of the covers look really ugly to my eyes - but this is about capturing that house style so that your book will not stand out as self-pub, not about looking classically stylish. And I do appreciate not having to squint to read the titles.)
I think all the covers you posted would fit under the exception I mentioned for books that are trying to sell a brand rather than a particular title, though. The US also has publisher series of reprints of classics that do that kind of thing. (And some academic presses that put small-audience specialty publications under standard covers.) They're not trying to sell an individual title, though: they're trying to attract people with brand loyalty, who already know they like that publisher's reprints and also already know they want that particular book.
For a selfpub author or small indy press with no brand loyalty, who's trying to attract people who've never heard of them or who have heard of them but don't want to put a lot of effort in to find a book, that's not really the marketing style you need to emulate. (Or. I mean. It could be; what do I know? But it won't make your book pass as a new release from a large NYC house.)
Also the first two of those covers look like they were printed in one color of ink on dyed paper? Which is something that was a lot more common in the mid-20th century, when printing with limited colors of ink was significantly cheaper and easier to do than full-color processes. That's not really the case anymore; full-color photo-quality printing is cheap enough that even books with only two colors on the cover almost always use the full-color process, and trying to mimic the covers with limited color looks like you're being deliberately vintage. (And again, that might be what a selfpub author wants to do! But these days, unless you have a huge amount of brand recognition, it's going to make your book look like a hipster small-run chapbook.)
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I think all the covers you posted would fit under the exception I mentioned for books that are trying to sell a brand rather than a particular title, though. The US also has publisher series of reprints of classics that do that kind of thing. (And some academic presses that put small-audience specialty publications under standard covers.) They're not trying to sell an individual title, though: they're trying to attract people with brand loyalty, who already know they like that publisher's reprints and also already know they want that particular book.
For a selfpub author or small indy press with no brand loyalty, who's trying to attract people who've never heard of them or who have heard of them but don't want to put a lot of effort in to find a book, that's not really the marketing style you need to emulate. (Or. I mean. It could be; what do I know? But it won't make your book pass as a new release from a large NYC house.)
Also the first two of those covers look like they were printed in one color of ink on dyed paper? Which is something that was a lot more common in the mid-20th century, when printing with limited colors of ink was significantly cheaper and easier to do than full-color processes. That's not really the case anymore; full-color photo-quality printing is cheap enough that even books with only two colors on the cover almost always use the full-color process, and trying to mimic the covers with limited color looks like you're being deliberately vintage. (And again, that might be what a selfpub author wants to do! But these days, unless you have a huge amount of brand recognition, it's going to make your book look like a hipster small-run chapbook.)