[spec] Limit valid encodings of text/gemini to UTF-8

[Petite Abeille]

> On Dec 30, 2020, at 03:31, Peter Vernigorov <pitr.vern at gmail.com> wrote:
> 
>  “3.3 Response bodies” and talks about any text/* responses.

Actually, this is counterproductive, and wrong, technically speaking.

Consider the following response:

20 text/html
...

While HTML5 is UTF-8 by default, most vintage html is ISO-8859-1. And there is a lot of vintage to go around.

Defaulting to UTF-8 for all of text/* at large would break the interweb as we know it.

Why take on such burden? 

Perhaps best to narrow the spec to only speak about text/gemini. 

Other text/* media types have their own idiosyncrasies. Best to leave them alone.

±2¢