Humans love novelty, it's what got us out of the cave, if you look at studies on boredom, they lead to sadism, that's how much humans hate boredom. When new ways to create become available, the people who struggle are often the ones who are unable to adapt their mindset to the new creative mediums and don't think "what is new to be done here" - I know nothing of the math word, actually I'm in awe of it, I have dyscalculia so I am blind to numbers etc, but I would guess that there will always be physics to explore, so there will always be math to be done, just, much like art, it will change?
AI becomes a new tool for creativity, and there will always be creative humans working to escape the pain of boredom.
But did photoshop, 3dsmax, digital photography or similar ways to print to photo paper or canvas prints make painting irrelevant? No not at all. The dentist lobby paintings got replaced cheaply but it made real paintings worth more.
AI is no different.