Perhaps not the very top level, but on the https://standardebooks.org/ebooks "Browse Ebooks" page, both `fiction` and `nonfiction` are readily applied as filters. Easily done.
Agreed, also with OP. I'm not sure why Alex didn't mention that the original publication date (or date range) is a standard item in the `content.opf` file that is part of every ebook.
This data is important to me, too, when choosing ebook—e.g., reading Dickens or some other prolific author in order of publication. The edge case for non-inclusion is a bit of an outlier–itself readily solved by using range, as noted (and producers already can do a fair bit of research when producing an SE volume!). (Conversely, the date of publication of the SE edition is of no interest to me at all...)
For personal interest, I maintain a "cumulative index" of the SE corpus which includes the original publication date, scraped from the `content.opf` file. Anyone interested is welcome to have a look: https://www.sudalyph.org/seci/