Simplistic (adjective)

1. Excessively simple and lacking complexity.
2. Tending to simplify complex issues or problems.

Origin:

Early 20th century: from simple + -istic.

Examples:

1. The explanation was too simplistic to be convincing.
2. The solution was simplistic and didn't address the root of the problem.
3. His approach to the problem was simplistic and not well thought out.
4. The book was criticized for its simplistic portrayal of the issue.
5. The movie was criticized for its simplistic plot.