The examples just show that Forth is useful for programming a DOS-like system.
If this is your honest opinion, I think I have little to discuss with you. I really don't think you wanted me show my code, you just wanted to make a point of some kind or another.
Forth has no limitations. It can be applied to any problem. It can be made as fast or slow, as small or large as the programmer's capability. I don't think any amount of discussion with you will get that across.
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tk, it is your loss. I don't care if you ignore Forth. The people who are actually going to do anything of substance with it, are the people who see the potential in the tool, and conceive of new creations before they exist. I don't have to see the 500 line VLSI cad program (or any other program of great complexity) to know it can be created.