I also do not understand this extra effort required in plain text files like NEWS.
It definitely going to happen that people will quote stuff as `something' (instead of using the curly quotes) and then we will have inconsistent quotes. Then we will need a script (like what Paul is doing) to convert those to curly quotes.
Instead, why not just stick to plain ` and ' in such files?
I have got to accept the curly quotes rendering in places like Info page rendering, stuff showed in echo area by messages and in the docstrings shown for vars and functions. There, the source code still uses ` and ' and there are *rendered* as curly quotes.
But in this recent commit, the curly quotes are being hard-coded. The only concern is that they are not faster/natural to type (inspite of having key-bindings to do so) compared to typing ` and '. And so we are bound to have mix of curly/grave/staight quotes in NEWS/etc. wherever we choose to hard-code the curly quotes.