The reason I do not simply set the umask to a fixed value is to use the same principle as upstream. That is honor the umask set bu the user. There may be reasons why group read and/or write should be set for example.
I agree with upstream that the umask should be honored, but not as strictly as upstream do. This is why I just override the "world readable" part and let the rest be controlled by the user.
In the working patch you can see that I also set back the umask (just a little further down in the file) as it was to just change this specific case of logging.
More clear now?