I decided to try and get some facts and do the math on it and this is what I found.
Using data provided by apple we can roughly calculate that each iphone/ipod touch user has downloaded an average of 36 apps(1.8b/50m), which only amounts to 2.25 pages of apps plus the default apps. So unfortunately it looks like you may be right, meaning that we probably won't see an update related to this (at least anytime soon), at least we can jail break though.
I guess this could also help to answer the OP's question of why apple hasn't done anything.
On the flipside of your logic, there are probably many people like myself that doesn't put a lot of apps on the phone BECAUSE of the omission of a filing system.
I just don't want to see 10 pages of apps and have to look through them to find what I want and also don't want to have to recall all names in order to search for them.
I really would love to put more apps ON the phone but it's just too cluttered even trying to use each page as a "category".