Of course as time passes, most things will be outdated by the minute. Nobody does the same thing forever. But some things are shook by the most profound changes. I think the music industry could be a good place to start, though it could also affect other industries.
On the subject of plagiarism, a scandal would be a big-game changer in how things are approached. I suspect that if musicians and producers were to avoid plagiarism they either come up with their own ideas, rely on a pre-existing catalogue (without copying it) or the public domain.
Plagiarism’s a no-no but could spread to the fashion industry. What could happen is a big DIY industry like before where you have websites and apps instructing people how to make their own clothing to be up to date with the latest trends and where to find those fabrics and patterns.
You could copy a Gucci dress as long as it’s personal and you don’t sell it. It could adapt to other industries to minimise the risk of plagiarism.