Why you should do a competitive analysis even if you see your work as "art" and not "product".
1. Inspiration
Other people making games/works on similar topics as you may be approaching similar themes or topics to what you are planning on doing them. Even if you do NOT like what they are doing and you become more confident in your own design direction.
2. Attribution
If you do like what they are doing and want to make something inspired or WORSE through cosmic magic have accidentally made something TOO similar. You can avoid plagiarizing by providing proper attribution.
3. Support
"Odds are if you are experiencing an issue, someone else has also" - someone on Stack Overflow probably.
By doing a competitive analysis you create a reference book of similar works (which don't have to be in your medium) you can turn to when issues arise.
4. Consumer Expectations
If something is repeated across multiple competitors you can bet consumers will want to see it addressed in your product.
When we see a zombie movie, we expect zombies to die if you shoot their brains. Knowing consumer expectations also helps you subvert them.
In Conclusion
Overall by doing diligence by performing a competitive analysis you can strengthen your design opinions, avoid plagiarism, and even find new ways to improve the originality of your work, all without considerations of making your project "profitable".