When studying geometry or anything else that involves lots of drawing, we often use the word 'visual'. But why not 'spatial' instead? The visual is only one out of many approaches to deal with space. We can explore it with our sense of touch, with our ears... Even with our sense of smell.
Visual space is only part of the story. Denying ourselves the opportunity to use other senses only because our eyes are, for now, working without any problem, is already a type of blindness. Have you ever tried to play a game, say Hex, without using your vision? The day I tried (and miserably failed) realised that the more I see space the less I am able to build it in my head. As if vision kind of outsources space from you.
What about exploring web, gopher and gemini spaces (surely I am missing others)? In web, heavy (maybe also light) designs usually are accessibility barriers, not only to screen readers but to those devices which, old or not, don't comply with the latest requirements. So is most ASCII art. Fortunately, the Gemini protocol allows you to enclose it with a couple of backtick triplets and write an 'alt text' textually describing it. This is one of the great reasons to use Gemini and not Gopher, which, as far as I know, lacks such an accessibility feature.
Regarding old devices which are not able to use TLS, Gopher seems better than Gemini, but let's not forget that for Gopher, only English language exists. The space of so many languages of the world becomes inaccessible with it. Could we dream of a Gopher with Unicode support or a Gemini without a TLS requirement?
Finally, how to explore a single line? Do you allow your text editor to introduce hard-coded line breaks? What if your readers use a screen narrower (with less columns) than yours? Your text suddenly breaks everywhere. Why not writing single lines unbroken by using your editor in a narrower window?
Space is not what you see or what I see, but what we reconstruct when interacting together within it. It requires to consider other perspectives, so what you build can preserve a robustness against any point of view. And, best of all, whatever you and I don't see, it can still be there. In other words: there are no spaces, only space, a single one shared by all.