[Deque]

If it's his first try in implementing everything, I wouldn't blame him. It's logically the correct decision, a start is a must.
I could never work on a full-fledged game of this kind because I couldn't finalize the gameplay.

This experience could benefit him very well, then he could start his own project with enough confidence.

You are right, of course. I don't blame him. It is just that I can't help thinking that the hard work could be used to create something new instead.
But yeah, I did the same when I started my first projects.