Tbf, that's not why the only or even I would guess primarily the reason why the startrek.website instance is used less. That was my first instance hop after Kbin.Earth died off (with that whole Ernst fiasco), and I abandonded it due to the very MANY technical glitches - like I remember making a post a couple times that did not make its way over to Lemmy.World for like a week, by which time of course nobody saw it, since even though it was "new" (to them) the time had gotten back-dated to its original, so it looked and acted like it had simply been passed over and ignored by the community previously, at which point it simply continued to be so forever.
Also seveal times I would write a comment but if I spent >1 minute doing so, then it would not let me post - though neither would it deny my post either, instead simply spinning forever trying but never succeeded, my only recourse being to copy and paste it into another window to try again, and hope to avoid duplicates. Sometimes even voting was problematic, requiring MANY presses and also waiting between each to see if it "took" because of the network issues.
Please note that most non-Lemmy.World instances were having those kinds of problems at the time, one of the multiple reasons being due to how Lemmy would send each individual item on its own (a vote, a comment, a post) rather than bundled together in packets of information, causing especially instances that are geographically far from Lemmy.World to struggle severely and be behind for weeks to MONTHS (aussie.zone was hit particularly hard). So I do not blame the instance admins for that, although the problem was more severe on STW, so I created what at first was an alt to use during the the times that STW was most problematic, but since Discuss.Online had such fantastic uptime, just started using it permanently.
Also I don't know if you are talking about Stamets or FlyingSquid or whoever, but I will note that the Tenforward community is now even more fragmented before, with a version now on Piefed.world (it is the #2 community located there), where ironically they decided NOT to put a link back to tenforward@lemmy.world (e.g. as a Sister community), plus they still call the new one by the same name, making it at least LOOK like they want it to become the new default?
Anyway PieFed has the ability to fight against such fragmentation effects by joining together all related communities into a single conjoined multi-community ("Topics" are made by admins and the "Feed" versions are user-customizeable and shareable!), see e.g. https://piefed.social/topic/tv-movies/star-trek that puts Risa, Tenforward, Daystrom Institute, and Star Trek all together.