When it is in a web page form, I do not call such thing "webcore";
I call it "vernacular web", which is a term coined by Olia Lialina who researched into GeoCities and 90s-2000s personal web scene. This term has been existing back as far as 2005.
But if we were strictly speaking of applying such aesthetics to
non-webpage media... well, have at it.
For me however, even that I am old enough to actually made GeoCities site back its heyday; the aspect of "retro" web that I'm personally invested into isn't the vernacular web aesthetics, but rather the technical side of it. While I could see many people in web revival movement expending their creativity in using modern technology to create sites with old vernacular web aesthetics;
I do the opposite, by coding modern designs
(1) using technologies of 1990s to 2000s-- in my effort to ensure information longevity.
(2)
(1) More precisely: off-modern mid-2010s designs.
(2) Current web technologies are suffering scope creep so extreme with moving-goalpost shifting so fast that it is considered a fool's errand to actually make a new browser from scratch that'd implement all of them in usable+compatible manner; so I swear off them and stick to properly-standardized (long-standing, with proper version number) specifications like HTML
4.01 (circa 1999; also known as ISO 15445:2000),
CSS 2.0 (circa 1998), and
CSS 2.1 (circa 2011), to make sure that people in the future can reliably reimplement a software to read what I make today.