The cut-off version was chosen arbitrarily. After doing 3.x I simply felt I could not be bothered with 2.x or earlier, and left them for InstallExplorer to handle.
quanta, you are welcome to add unpacking support for 2.x. If there are only minor differences, it should not be too hard, right?.
2009-04-23 18:28:23 UTC in Inno Setup Unpacker