iPhone: iOS 4.3 Update and Rebounce

Apple is officially leaving some of their old product behind. It's obvious that they refuse to give an update to some of their iDevice; if you are using iPhone 3G iOS 4.2.1 you will notice that you have the latest update when connected to iTunes but the fact still remain that you cant download and install some apps (designed for iOS 4.3 upward) from iTunes in this case you can only download those designed for iOS 4.2.1 downward this make me think perhaps Apple is indirectly telling anyone that has these iDevice to upgrade (purchase the higher devices 3GS, 4G.....)

If you are on iOS 4.2.1 try to install Facebook App you will get a massage of incompatibility and it's same with other applications that are writing for higher iOS (4.3 and higher), I know before now Facebook app was compatible with iOS 4.2.1 but as time goes on Facebook have to keep it up-to-date with their app and now you cant install Facebook app to your iPhone 3G because you are not on the right OS version for Facebook app...that means every other important application will soon become incompatible, as time goes on, because they will be updating too...I pray one day Apple will just release an update for iPhone 3G and others and if they don't give the update i think the only way to enjoy a non compatible app is by jailbreak this will unlock your iPhone so that other(unsigned) apps can be installed via Cydia instead of iTunes, and will add more functionality to your iPhone such as setting up a home screen wallpaper, enabling multitasking and more.

I would like to know your view on this opinion if you are facing the same installation problem or if you have a idea on how to twick iOS 4.3.1 in order to install these higher apps