>it seems the newer users do not enjoy such things.
Virtually all the other boards have seen a similar decrease in activity since 2020 (even more so since the April 2025 hack) - so it's probably not that /d/ in particular that's shrinking, but rather 4chan as a whole

That aspect in particular is probably a combination of it being near-impossible to post there these days (due to IP bans/distrust-by-default), the global increase in internet regulation/censorship, and that the kinds of people who would traditionally find the site appealing have either left for good or don't ever venture outside The Platforms