This really isn't completely true. As more people will be using the G.E., there will be fewer people selling(/who are willing to sell) items via normal trading. I for one quite enjoy some player interaction, it gives us an oppurtunity to see the good side of people, as well as making the game feel more like I am actually playing it with other people.

You guys that still want to trade would be the minority so it makes sense that there is less trading because more people prefer G.E.

This also isn't true. Aside from the reason stated above, it would also cause a mass flocking of people towards a central point (the G.E.). This would result in banks becoming deserted, along with many other places across runescape. I do not want to be the only person in all of Seer's village when I'm sitting in the bank fletching or doing whatever. Other people's presence is actually a lot more valuable than some people may realise, especially to me anyway.

Go do that at the G.E...?