What environment cannot render ASCII text but can render SVG? I think converting in the other direction could be a lot more useful.
This is useful in a plain-text based document system, for producing nicer rendered output. Box diagrams typed up in a man page can be rendered more nicely in a HTML version.
It could also serve as part of the markup input language in a system like asciidoc. The benefit is that the source resembles the output.
In this man page, I have lots of occurrences of
<-->
in verbatim code which could be turned into a nicer arrow.
Also, textual diagrams occur:
For displaying "inline glyphs" made of sequence of consecutive characters there is option to use font with corresponding ligatures baked in, such as Fira Code [0].