Usually if you play for a long while without inflicting more black marks onto your account, like say it's been 2 years, usually you could appeal it and then they'd take off some. Especially around the time they took Pking and all that out, I noticed Jagex unbanned, unmuted, and took off black marks on a lottttt of accounts lol, they just mass unpunished.
Just try appealing a couple times or sending them messages etc, it's been 2 years, you'd probably be able to take some off.