Here's how I see it:
In a world of unchallenged automatic HTTPS upgrades, cookie-cutter Wix sites, Google Chrome monopolies, unsolicited ad / tracking / fingerprinting servers, being pressured to use a Google / Facebook / Apple account to log into everywhere, and an endless supply of mainstream social media censorship feeds sponsored by our unelected corporate oligarch overlords ... consciously choosing to ignore the oft-traveled path of least resistance and instead manually write a website from a blank sheet of paper that follows none of the above values held by the majority of modern Internet users, is an objectively contrarian action.
Reasonably, if you then attempted to translate that scenario into a public-friendly brand or identity, such a term as "renegade" (for example; unless someone can offer a better choice if they are in opposition to its use) would by definition describe that outcome,
as per Merriam-Webster:
Definition of renegade
1: a deserter from one faith, cause, or allegiance to another
2: an individual who rejects lawful or conventional behavior
In this case, the second definition being especially fitting of what is going on here. You don't see most authors of these outlier websites parading around their Facebook or Twitter accounts, accumulated likes / shares / views / reposts, and noteworthy online followings (although I find the seemingly universal attachment to Discord concerning); they are proudly publishing badges, web rings, and portals pointed to other similarly designed sites, to assist the visitor in navigating through
that network of websites rather than the mainstream one, which is an abstract behavior that the current Web hasn't seen for the better part of the last 20 years, and not to mention a seemingly deliberate rejection of commonly-accepted mainstream methods.
Further, this does not appear to be a phenomenon with an exclusive focus to the past, but rather one that is influenced by history with an eye to the future. Therefore, since a bona fide "vintage web" already exists (courtesy of The Internet Archive's unmatched preservation efforts), it would seem more fitting to delegate this newer movement into a class of its own, and thus, an entirely new name.
But nonetheless, the purpose of this thread on MacRumors is to grow public awareness of this happening and encourage visitors to contribute, as well as to publish a suggested design standard (that happens to be agreed upon by over 50 individuals so far) in a bid to make this aforementioned unique network of websites operate more cohesively together. In the end however, people can call it whatever they want. One thread on some online forum can only hold so much power in practice.
@B S Magnet ... But please ... continue your judgmental behavior that contributes nothing and leads to nowhere.