I think it is rather because people have a misconception about what is ‘a world’ and he didn’t want to add to their delusion by answering speculative questions in a categorical manner.
There are these passages that i think are relevant;
[When this was said, the Blessed One responded:] “I tell you, friend, that it is not possible by traveling to know or see or reach a far end of the cosmos [loka] where one does not take birth, age, die, pass away, or reappear. But at the same time, I tell you that there is no making an end of suffering & stress without reaching the end of the cosmos. Yet it is just within this fathom-long body, with its perception & intellect, that I declare that there is the cosmos, the origination of the cosmos, the cessation of the cosmos, and the path of practice leading to the cessation of the cosmos.”
It’s not to be reached by traveling,
the end of the cosmos —
regardless.
And it’s not without reaching
the end of the cosmos
that there is release
from suffering & stress.
So, truly, the wise one,
an expert with regard to the cosmos,
a knower of the end of the cosmos,
having fulfilled the holy life,
calmed,
knowing the cosmos’ end,
doesn’t long for this cosmos
or for any other. An4.45
World is defined here;
That in the world by which one is a perceiver of the world, a conceiver of the world—this is called the world in the Noble One’s Discipline. And what, friends, is that in the world by which one is a perceiver of the world, a conceiver of the world? The eye is that in the world by which one is a perceiver of the world, a conceiver of the world . The ear … The nose … The tongue … The body … The mind is that in the world by which one is a perceiver of the world, a conceiver of the world. That in the world by which one is a perceiver of the world, a conceiver of the world—this is called the world in the Noble One’s Discipline. Sn35.11
I think this goes with Sabba Sutta
The Blessed One said, “What is the All? Simply the eye & forms, ear & sounds, nose & aromas, tongue & flavors, body & tactile sensations, intellect & ideas. This, monks, is called the All. [1] Anyone who would say, ‘Repudiating this All, I will describe another,’ if questioned on what exactly might be the grounds for his statement, would be unable to explain, and furthermore, would be put to grief. Why? Because it lies beyond range.”
I think that they speak about taking another birth as ‘next world’
And what is the right view with effluents, siding with merit, resulting in acquisitions? 'There is what is given, what is offered, what is sacrificed. There are fruits & results of good & bad actions. There is this world & the next world. Mn117
Finally there is that ayatana associated with a cessation of the world;
There is that dimension, monks, where there is neither earth, nor water, nor fire, nor wind; neither dimension of the infinitude of space, nor dimension of the infinitude of consciousness, nor dimension of nothingness, nor dimension of neither perception nor non-perception; neither this world, nor the next world, nor sun, nor moon. And there, I say, there is neither coming, nor going, nor staying; neither passing away nor arising: unestablished,unevolving, without support. This, just this, is the end of stress. Ud8.1