In my opinion, the art form that requires the most skill is classical music, specifically instrumental performance, while the art form that requires the least skill is casual digital illustration.

You have to be able to master various techniques and instruments in order to deliver a nuanced performance that resonates emotionally with the audience. It takes a lot of practice to achieve the precision and artistry required in classical music. The intricate nature of music theory, combined with the physical dexterity needed to play an instrument well, makes it very difficult to excel in this field.

On the other hand, while digital illustration can certainly be a complex and nuanced discipline, for someone looking to create simple designs or graphics, it isn’t that difficult to get started. With the availability of user-friendly software and online tutorials, it doesn’t take much practice to produce basic illustrations. Many individuals can quickly learn the basics and create satisfactory works of art without extensive training.

In conclusion, classical music demands a high level of skill and dedication, making it one of the most challenging art forms, whereas casual digital illustration can be accessible to beginners and requires relatively less skill to achieve basic competency.