I like this comment. It touches on what makes creating art for OSRS so challenging.
To give you some insight into how I'm approaching it; It starts by taking an honest look at the asset catalog without any mental filters or personal bias. A proper look at the shape language, topology, colours etc. Then once that familiarity with the catalog in established, the next step is to look for 'medium' design trends. The through-line that ties it all together. This step is especially challenging for OSRS as so many artists have had a hand in the IP throughout the years with so many private ideas about what the game is. At this stage you'll have a 'general' idea of what's come before and how to dance in step with it. West has mastered this part of the process and is half the reason he can instinctively build assets for OSRS. The next step is to introduce very cautiously your own personal attraction to the game, and along with that, with empathy, the attraction that different groups in the community find towards the game. This step is one of negotiation and co-operation and takes time. It's especially difficult reconciling conflicting viewpoints within the community. If done right however, new designs can be introduced with new briefs, saying new and interesting things without feeling completely out of touch with the greater picture.
There's a lot more to be said for the limited tech challenges too, accepting them as the style guide parameters rather than denying them and designing for 'the high tech game I wish it was'. That's a defective view for an OSRS artist to have. Point in case here is to check out the original Torva concept art. Everything in that design is solved for a PBR workflow, once rendered down into a matte texture like RS3 has, it became something else, then something else again once rasterized down to OSRS. I have a real problem with that, and for that reason concepts for OSRS are literally drawn from topology up.
This job isn't for everyone. It takes a certain kind of masochism to pay your rent under these pressures but when it works out and we're all happy, it's ace.