From having a look many of them are just a small linktree to larger websites where the information is.
I like the idea of keeping things lightweight, but if I'm being pointed away to external sites for everything. Then it's mostly a 1kb webpage as opposed to a website.
1kb is just not practical for pretty much anything.
None of the sites in this 1kB club even attempt anything noteworthy.
For example, one of them just says “persons name, web hacker”. Wowee.
After reading some of the negative comments here, I followed the link and clicked on about 7 of the pages listed, each in a new tab such that the successive pages may load (at least in part) while I browse the others. What follows is my first hand account of the things I saw in those about 7 tabs.
I saw a bunch of simple (yet distinct) pages, most of which looked to be "business cards". There was text which was not only legible but of varied form and colour while remaining so. I found that some of them even had style, though nary a sheet was found!
[Here I must warn you: what follows is so sensational you may very well accuse me of tomfoolery. You have been warned.] Some of the about 7 pages I viewed gave me the impression that the people who made them were having fun, or at the very least enjoyed the creative process. One of them[1] lets you insert your own buzzword!
[^] kilo or kibi? does the club care? is 1kb 1024 or 1000 bytes? is a byte 8 bits long? big or little end? I don't know, I am not really a real web developer
[1] https://hi.gy/
You might be interested to know that I was also wrong to act as if there was an air of mystery surrounding the definition of '1kb'. It's readily apparent that the '1k' refers to 1024, as it always has when speaking of bytes, but also because the first (some would say only) sentence on the 1kb.club page helpfully spells out that 'kB' is short for 'kilobyte', and that a kilobyte is 1024 bytes.
A club for websites that only show a single character, forget about the HTML doctype