

In case you might be interested, there are a handful of private-servers for old school RuneScape. And they usually give you the ability to choose an XP multiplier. 2009scape for instance, gives you a 5x multiplier by default.
They’re not 100% complete recreations, but they add more quests all the time and I believe they have most skills.
Worth checking out imo. You can even download and run your own copy of their server (with some effort), and then you can tweak literally anything (again with effort and knowledge of Java)



Fair, I guess at that point, it might just not be the kinda game for you. It is grindy by design, the official game, of course, wants you to stay in the game longer so you buy more subscription time.
Idk, I enjoy playing OSRS on occasion, they added sailing as a skill, and honestly it was pretty cool. Having your own boat and being able to freely sail around the entire map. I mostly play for the nostalgia though.