That’s true if you’re familiar with programming and know how CloudFormation works. Adding a framework or abstraction layer requires certainly more skills from your end. This article is more suitable for people who want to deploy small projects quickly and don’t want to invest time to learn a framework.
CDK is significantly more comprehensible than CloudFormation. Particularly: it has patterns and convenciones baked in that let a few lines of code translate into 100s of lines of CloudFormation