Zirconiansaid: Jagex should take all the stuff sold to shops that players could use for exp rather than see it go to waste because of the lvl and try to give more keys because of that reason.
What you're asking for is the removal of item sinks, which would simply add to the oversupply of resources existing within the market and driving their prices down. This would make skilling a lot less profitable, but simultaneously make skills faster and easier to train because of cheap resources being available.
I don't know what you mean by keys, but if you mean excess items should be converted into Treasure Hunter keys, that's even worse than the above because that would over-saturate the game with Treasure Hunter keys and make them too easy to amass for free - people would never buy them with real money again, if they can simply chop oaks for an hour and get lots of them. That would drive down Jagex's profits, meaning they'd have to push even harder with MTX and make it even more obnoxious.