> Plain text is friendly towards developers. But it’s neither interop-friendly nor user friendly.
Kind of got off track here. You can process a lot of formats as text (html, css, xml, etc). So a BOM there is unnecessary and sometimes detrimental. On the unix side there are a lot of text utilities that do useful things that you can do on these formats. That's probably why BOMs are non existent there.
> MS can’t change the compiler because backward compatibility.
You care to tell MS that? Every single time I've done a major VS upgrade my code had to be changed because something that was valid before stopped being valid.
> And there aren’t any.
If you can't see any benefit of using UTF-8 then I'm done debating with you.
The trend towards higher-level data formats is universal across all OSes.
Even on Unix, users typically read html, write odf or docx both being xml, print PostScript, etc.
Plain text is friendly towards developers. But it’s neither interop-friendly nor user friendly.
> Visual C++ off the top of my head
Only the C++ compiler. MS can’t change the compiler because backward compatibility. The IDE however works fine with such files.
> "UTF-8 Everywhere" site is trying to promote.
The transition is going to be expensive, because most languages and frameworks (C++/MFC/ATL/QT, .NET languages, JVM languages, Python, etc) use Unicode (USC2 or UT16) strings for decades already.
To justify the costs, the benefits of the transition must be substantial.
And there aren’t any.