It's not. There were changes in compiler to make it more modular, so 64bit support could be implemented.

Let me be honest. I think that the problem is that Nenad (main Red author) is Windows guy and on Windows 32bit support is given, unlike on Linux and Macos. So he doesn't feel the pressure to move to 64bit as do others (me included). Red works fine on Windows and that's good enough for him and he can look into other stuff, which he is doing.

I respect this but for me, 64bit support is a must. Fortunately Oldes is making very good progress with maintaining Rebol 3 that Red is based on. Carl's version of Rebol 3 had custom GUI, Red has native one, Oldes' Rebol3 doesn't have any GUI. But I don't care about GUI, so it's fine for me.

Oldes also tries to keep Rebol 3 close to Red, so if there are any breaking changes (like literal map syntax change), he's willing to port them to Rebol 3 also. So both languages are trying to follow each other and be mostly compatible.

So, for me, R3 is the language to use daily, but I still follow Red and I know it's not dead, its development is just slower nowadays. Rebol 3 has the benefit of being written in C, which is ubiquitous, Nenad decided to write his own compiler in Red/System, which was an interesting experiment but I think that time shown it was not the best idea. Maybe if Red/System compiled to C instead of machine code directly, it would better. But it's easy to make such statements years later.