Learning Photoshop can help hone your skills and creativity. It might not be designed keeping amateurs in mind but it does have some significant features that can help even first-time users while they start out.
Adobe Photoshop is not a free software and hence it is more beneficial for professionals that beginners. There are other free tools available for editing images but it would be tough to match the capabilities of Photoshop.
Being well versed and proficient in Photoshop can be an advantage if you are looking for a job. It would be helpful to make you stand out from the crowd. It could also be effectively used for your business needs.
The benefits of Photoshop are many and it would depend on how one chooses to make the most of it.