I wouldn’t say there is anything specifically wrong, but rather incomplete or misleading.
For example, only now (and thanks to you) did I realise that the first example of “Configuring Dependencies” section puts “implementation” inside “dependencies”.
My argument would be that the article sounds like a quick intro to the topic but then it’s too exhaustive. I ended up spending quite some time trying to find a minimal “hello world”-style build.gradle(.kts) file - made worse with my other issue causing me to doubt when the setup actually works vs just some IDE complaints.