I don't think that fashion trends are comparable. I think that fashion trends are fine in concept–things get old and we switch things up. It's the way the human superorganism is able to evolve new ideas. Unfortunately, capitalism accelerates these changes to an unreasonable pace, but even in Star Trek communism, people get bored. The cultural energy that birthed one style is no longer present, we always need something new that appeals to the current time.

But clothes still have to look nice. Fashion designers have a motivation to make clothes that serve their purpose elegantly. Inelegance would be adding metal rails to a skirt so that you could extend its length at will. Sure, the new object has a new function, and its designer might feel clever, but it is uglier. But ugly software and beautiful software often look the same. So software trends end up being ugly, because no one involved had an eye for beauty.