As some side context, it's also worth considering how Homestuck was written and released as the very tail end of the "golden age" of webcomics. It's perhaps a little difficult to fully picture it now, but in the late 90s and the aughts, webcomics were the The Thing on the internet -- there are individual comics with dedicated fandoms now, sure, but back then there frankly wasn't much in online culture that wasn't involved with or at least clearly aware of most major webcomics. Like, we joke about all the old two-gamers-on-a-couch things now, but back in their day things like Penny Arcade were one of the primary ways that people got their commentary on gaming.
(There's another post I've seen floating about commenting on how TV Tropes is filled with references to webcomics from the 2000s that nobody's ever heard about, and that kind of misses the thing that most of those examples were in fact written in the 2000s when a lot of people cared about that!)
So to circle back to the Homestuck as a period piece thing, I think that it's very interesting to note its "historic" placement -- one of the very last of the really, really high-profile, widely-read internet comics, written in the 2010s and looking back to the very start of its period of internet history back in the 90s.