Yeah, botting in general is dying, however there are more people on OSRS now due to F2P opening up.
I gotta agree with @Dashboard. When it comes to bot detection there are so many things bot developers have to account for there's a good chance at least one is going to slip their minds. Even something as simple as subclassing the Canvas for that bot paint overlay you guys all love is asking for a ban if you don't do it right. Jagex literally just has to send a superclass request and if they get something like "Lorg/osbot/BotCanvas;" back it's a dead giveaway.
Obviously there are ways to get around this, like routing requests such as these to the unmodified jar using a separate class loader, however then comes the issue of giving the correct response back (NoSuchMethodException instead of a null value for example). One incorrect piece of data is a flag to Jagex that you're cheating.