These days, the drawing an exact likeness doesn't have as much point, but the underlying skill certainly does.

If you can legitimately draw photorealism (as opposed to sectioning and carefully copying a photo), then it represents a deep understanding of how natural phenomena affect form, the consequences of physics anatomy on body shape, and how shape affects light and perception.

Mastery of these concepts is prerequisite to creation of new works. How does having wings change a character's anatomy? Extra arms? How do you create buildings that look plausible yet alien? How do you create new garments that have believable textures and draping? Skills that are useful for cinema, for design, for editing.

The photorealistic drawing itself is probably of little artistic value, but it's a step towards creating realities that don't exist.