I will summarize the relevant argument for people who may not read the entire thread.
The proposal:
This statement exists in DBZ anime. As the episode comes to a finish, the narrator ends it off by saying
"Separated by time and space, the harsh trials that the sleeping father and son must face continue on and on."
Goku is in the afterlife and Gohan is on Earth, and they are said to be separated by time and space. Taken literally, this would imply both realms have their own space-time continuums, making a universe in DBZ anime a 2-C structure.
My disagreement:
We treat the anime as being separate from the manga because it adds a fair few things on its own. However it is still an adaptation of the original manga. And the exact same scene exists in the manga with a similar dialogue by the narrator.
The original chapter in the manga ends at the same scene where the episode in the anime ends.
The narration states this in the very next page of the manga. "On Heaven and Earth, Goku and Gohan's training begins!!! Two generations, two kinds of training"
The above context is important to know where the statement actually came from. Because the chapter ends exactly where the episode ends, and the next chapter starts with the similar narration that is used to close off the episode. It's obvious both are trying to go for the same thing. This context is supporting evidence for my main points:
1. They are poetic dialogues meant to smoothen a transition between two chapters/episodes. The anime just adapted it up from the manga and changed it a little bit.
2. One could claim that the anime has it because they wanted to emphasize that both realms are separate space-time continuums. However, the statement is not part of any explanation regarding the structure of the universe. It is not part of any exposition dump regarding what the realms are or how they work. It is part of the same poetic sentence that talks about Goku and Gohan needing to go through harsh training. Which leads me to believe that is was never meant to be taken as a fact-based statement, but it is a throwaway statement which was never repeated or confirmed later on.
3. The original statement has the words "two generations" referring to Goku and Gohan. The adapted statement has the words "separated by time" referring to the same people. It is entirely possible that this "separated by time" part is not referring to space-time continuum shenanigans, but the time difference (age difference or generation gap) between the father and son. The "separated by space" part would just be an adaptation of 'On heaven and Earth" part, referring to the two realms.
Whatever may be the case, the statement in itself does not seem 100% reliable in the context of the realms having separate space-time continuums, and such a huge change should not be based on a questionable statement like this alone. At best this can act like a supporting evidence for some other concrete information that should be acting as the primary evidence.
@Promestein what do you think?