[Shujin]

Its not nessecairly grudges either, I would say. It the fear of having your stories interrupted.
I have played SL2 on and off for I think nearly 5 or 6 years now (Time flies, I know I tested the early alphas and a bit of SL1 and have been around since). From my experience SL2s "RP Focus" simply changes with the time and it has different "Phases". Some eras went like that, the others were mirror images of that.

I felt early on people were MUCH more content with not being maxed out, just writing out their characters and dip in it. Write their stories and interact on that without nessecairly worrying too much about builds.

One huge shift in RP mentally followed the great reckoning were everything became more "Convieniant", more simple. While we got a lot more tools to play with it also became its own little contest of SL2 mechanic rocket science to find the most fun and effective builds and everyone was more "Even" to the lack of RNG in level up rolls. As good as that was it came with a side effect of accomplishments being reduced by a lot and now every 12 year old kid is secretly a hidden pro warrior.

Then people started to flock to PvP as a resolver of most IC conflicts, and as much fun SL2 is if you play it right? Using PvP as its only way to resolve a conflict has some massive flaws as you can easily cheese a build just for Power and everyone who plays a character that just fits their IC is (And that doesn't feel rewarding to stick to your guns in an RP just to suffer that.)....Pretty much screwed as they can't compete. This fear a lot of people have be it just because they do not feel confident in building or just do not want to have their RP shattered by try hards with Meta builds is a persistent one which is very visible in the current state of the game.->

The balance is heavily shifted in favor on one specific play style. Doing anything big in public that is not Slice of life and basic Arena doodleing can quickly end up with someone popping up flexing their meta build and...Boop. GG guys! Was fun working out this 8 stage story, aye? Glad that random guy(/s) showed us that cookie cutter build and cut us off at stage 2. (And don't get me started on the guard system and people metagaming across their 43 characters.)
So obviously people enjoy both RP and the Combat far more if its within their own supervision with more fun and various build and the "meta builds" reversed for challenging "boss fights".

I am not saying everyone is doing that, but the fear that just ONE does it and can cancel all your hard work is enough for people to go certain to not public that stuff...So what have we created? A world were people play all their own lores and Stories, away from everyone but their own friend circle because not a single one of the systems in place gives you a reason to engage with the world, because the world is Stale. Period. Never once did anything happen in the world that left a lasting impact.
(Cellsvich doesn't count. It was convienitely did that way because we had a new map, not because it was worked towards it and even that just gave a little bit to chat about. The other "big" thing was bloeden trying to go for the Emporer and that got us a nice little speech followed by bloeden execution..Hardly any big events that most people do not even know of)
And the system in place just punish you OOCly for doing it (See guard system. Not saying they shouldn't be there but its one heavy weight on a scale that has no counter part)


So I stick to what I have said for years. SL2 is a game you play either Casually for slice of life with alitte combat. (which just isn't everyone cup of tea if that's all to it) Or a game you play within a friendcircle that's already established that you grow into (which can be hard in and on itself. I have seen lots of newbies give up trying that, cause they didn't get "in" quickly enough and felt lost in the game. While I did try to pick some by the hand and lead them somewhere many just drop in and out under the radar too.))

To me the world feels dead, outside of the stories I do myself. But I do not need to play SL2 to make my stories even though I love the game, its more restricting than helping and the RP is flat out better in Discord. But that's just how the current "Era" is. I am positive that changes once the Combat is fixed again or when stuff is added that makes you feel more important or interacting with the game world/Lore....
SL2 has one big issue that it had from the very start-> The story was never about you(general you), you are just someone tapping along and watching from outside making you feel insignificant while the world builds veeeeeeery slowly. (Heck black bleasts are still attacking and the church keeps playing cards at Risus for a couple of in game decades now.) So you never feel the story having anything to do with you. its just kinda there.

Thats the main difference I notice with SL2 and other more popular Byond RPs.

In short:
-Convienance, laziness from the players, Win mentality , lack of interaction/response of the world made this game less and less attractive for people that plan to stick a lot of time in it.
Slice of life can be fun, but when its the only viable thing to do while you have such a cool lore and stuff to play with, is quickly making you lose interest and only pink tinted googles/friends really keep you there.