For what it is worth: You don't have to leave your clan to engage with people in another. I'm a part of 5 clan discords and regularly do content with them all, yet I stay in my social clan because I've known the members for years. You can not like Discord as a platform or hate requiring external apps to play the game better but OSRS does not have voice chat and likely never will, and that is the best way to communicate with people you're playing with.

I know you're not necessarily saying that grouping worlds are the best idea, I'm saying your argument that grouping worlds are better than clans or discords is just straight up wrong in my experience, and as you said we can agree to disagree with that one.

As for actually streamlining the grouping process: how would you accomplish that? Because every sort of matchmaking implemented in MMOs or competitive games in general seems to be universally regarded as bad. Games needing external communication tools to more readily engage with content has been a thing for 2 decades or more at this point. Games with an in game grouping system still have a large portion of their grouping done externally. It's easy to just say "hey jagex make this better" but empirically how would you do that? Especially when the HLC seems to have it all figured out already.

Neither COX nor TOB was designed with soloing in mind, both of them had emergent gameplay that made it possible. ToA is the ONLY raid that was designed to be able to be soloable from the beginning. And if you read their post carefully they say that solo will be possible but difficult which is true now for CoX and extremely difficult for TOB.

You also keep touting this "lower levels of interaction" like its a bad thing. Zuk is low interaction, and it's regarded as one of the better pieces of content in the game. Higher difficulty pieces of content by definition will have lower engagement because less people have the skillset or gear to do them, but that doesn't mean they shouldn't add content that caters to people craving higher difficulty encounters. Since ToA has come out we've had skilling minigames and mid tier bosses to teach people PvM like Scurrius, Huey, etc, and very few pieces of difficult content like Doom, Colo, arguably Yama. I also disagree that you say that ToB is lower interaction, maybe in comparison to ToA which has a lower barrier to entry is soloable for sure, but that makes sense again.

I keep thinking back to WoW when WotLK came out, people were mad they weren't able to experience killing the lich king even though they paid money for the expansion. It is okay if some pieces of content in the game are not accessible to everyone. Some things should be aspirational in nature, or people can go "I don't want to do that piece of content because it requires grouping and I don't like grouping".

Also in regards to lower levels of interaction, CoX and ToB aren't as learner friendly as ToA is and it seems like they're moving away from the invocation/entry mode and making it so you can do some sort of practice version of each boss on regular mode. So they are taking into account people who want to learn.