Bartok samples from Shostakovich and it's called "interplay between serious composers" but someone does the same thing on a computer and it's the end of creativity as we know it.
The creativity is in the mashup. Yes, the linked video is made of individual pieces the video maker didn't create, but the final song never existed without the video maker putting it all together. It just reinforces my believe that you have narrow tastes in music and little appreciation for anything that challenges your preconceptions.
Get off your high horse and realize that there's more to creativity in this world than what you happen to like or accept. All you're arguing is that the only way to create music is the way it's always been done (or more specifically the way it's always been done professionally). There's so much more to art than that.
Netflix is based on suggestions. It's always suggesting you watch thing and it's navigation menu is almost all suggestions. It's pretty easy to just click and watch something at random, and if you've rated enough content, it's a fair bet it's something you will enjoy. Works pretty well.
We already collect taxes and give it to artists. That what the National Endowment for the Arts is for. If people want more of that, I'm all for it. Let the artists apply for grants and keep the for-profit corporations out of it.
After all, why can't a rock musician get paid the same way a symphony musician does?
The goal of art is not to create something new and original. The goal of art is to contribute something to the conversation. Every contribution enhances the conversation and if enough people contribute, it becomes a piece of culture. That's what made rock and roll a thing - lots of people doing it - and now rock and roll is a part of culture.
All the new and original stuff does is change the conversation, which is what makes the new and original stuff important. Most art does not do this.
And in today's world of pop culture, much of that conversation revolves around the copyrighted content of others. That's why having a robust public domain is necessary. Copyright stifles the conversation we call culture for the sake of profit.
The ridiculous thing is that if Thicke really wanted to copy Marvin Gaye, he could have easily just paid a licensing fee to do a cover like lots of artists do. The fact that he didn't shows that he wasn't intending to copy.