If the design is optional, why does Reddit have an 80k CSS file and Craigslist have a 14k one? (Admittedly, HN has a very tiny amount of design).
Design isn't necessarily about embellishment, but aesthetic choices. Good typography and color scheme choices don't have to be paired with elaborate graphics for a design to be good.
But more to the point of what you're saying, design is NOT optional. It is the essence of how people interact with your website/product. There are certainly some exceptions to the rule, but generally people flock to a more attractive product because it is attractive. Look at any Apple product for a perfect example of this. iOS is far less usable and powerful than Android, but people like it more because it's visually pleasing. OSS is never going to win unless it has that similar level of sex appeal in its products.
Design isn't necessarily about embellishment, but aesthetic choices. Good typography and color scheme choices don't have to be paired with elaborate graphics for a design to be good.
But more to the point of what you're saying, design is NOT optional. It is the essence of how people interact with your website/product. There are certainly some exceptions to the rule, but generally people flock to a more attractive product because it is attractive. Look at any Apple product for a perfect example of this. iOS is far less usable and powerful than Android, but people like it more because it's visually pleasing. OSS is never going to win unless it has that similar level of sex appeal in its products.