I've also been using 'Linux' for close to 20 years. I put it in quotes, since Linux is just the kernel, and it's the multitude of userland utilities that you actually use.
The file hierarchy system, I'm guessing is what you're referring to? Actually I'm not even sure what your comments were talking about. When I started, the first thing I learned was the file hierarchy system. Once you've learned that it's EASY. Besides, it is very Unix, as is the AmigaOS. Actually a lot of the 'inadequacies' that people talk about with even the newest Linux distribution is "why do I have to do that with the terminal?" Because it's just the most efficient way to do some things. Even in AmigaOS, there are tons of command line software. It's useful, to say the least.
Anyhow, to answer the actual original post, you can get an Amiga Look & Feel. It can get pretty close, but just not quite spot on. There are themes for GTK (Gnome based) as well as Qt (KDE based), but most of that hasn't been updated in a while, so newer distributions will use the newer versions of gnome/kde that haven't had the themes upgraded for them.
There is a window manager called amiwm that makes the window borders look like the Amiga. And someone has 'ported' Ken's Icons (the ones from AmigaOS4) for the Linux desktop environments.
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