A big one would be alching. High alching single handedly prevents any item from getting worthless, and until you write a composition how I'm incorrect, I oblige you to discover an item at which the buy-able G.E cost in addition to the cost of 1 nature rune is less than the high alch value of said item, and stays that cost for more than 24 hours. If what you're saying were true with OSRS gold, all of longbows are unworthy, but thanks to large alching, their prices have remained stable.

To say most abilities are useless at runescape is a statement if you expect there to be no upgrades to the game. As an instance, let us say a new ore that requires 95 mining to collect is added by RS, and it is 10x more precious than the usual ore. If you only had 85 mining since runite ore and never leveled past it, you would need to spend a loooong time to have that 95 mining requirement to mine the new ore, provided that in fact, that the prices of the fresh ore will have spiked significantly by the time you reach 95 mining. All of the gamers using 95+ mining will probably be putting the prices for the brand new ore, and will have made millions if not billions of gp by the time you buy 95 mining and the costs drop. So yes, it's beneficial to train past the grade of gatherables/craftables.

The mmos that lack an auction house and participant trading could be counted on one hand. If buying/selling you put a bid the market deems fair and expect someone agrees with your assessment, it is 100 percent only an auction house with an anon attribute

You can try to paint it however you'd like but when it was launch it was even billed as a auction house with cheap RuneScape gold.there is a reason the price setting has been removed, things have a particular value that many player either know or look for before purchasing or selling items, if the value isn't what is predetermined by the players (not jagex) the thing will never be on the GE.this second point is fucking stupid, flatout unequivocal stupid.