Probably there's also less effort in collecting and making this content available.
Fans almost always say they prefer the DC (or actually the "Final Cut"), but my theory is that their opinion isn't really valid because they all saw the theatrical version first, so upon viewing the later cuts, they had the benefit of already knowing the story and background, and of course they can't just forget that when watching a voiceover-less cut.
So, I've never actually seen the theatrical version with the voiceover. However, I don't believe there's anything in the film that I don't understand. I understood the symbolism and the message that was being conveyed. I'm being deliberately vague here because I don't want to spoil it for any random reader who might see this.
I don't think there's anything particularly difficult to understand about the film. Perhaps you think I am giving people too much credit? I don't think I am. There are lots of films out there with deeper meanings and hidden ideas/messages. There are lots of very critical viewers out there who pay attention and don't need everything spelled out for them. These are also the people most likely to get annoyed when a voiceover spoils it for them.