you're missing the point. lol
literally all you had to do was not be a richard about it. thats it. you could've told him the same exact thing you said but in a way that doesn't come off so aggressively
im not sugarcoating anything at all. there are only two things this project can be: good or bad. by saying that i'm wrong or a richard for saying it's bad, you're basically admitting that this project is good. anyone who thinks based on any of the information OP gave that this game is good in any way is basically either 10 years old, incredibly loving overoptimistic, or just delusional.
you could argue: the game isn't finished! why are you judging it so harshly?
the simple answer is that if your first phase of game development (the idea phase) isn't clear or understood enough by the developer to actually communicate what the game is about in an engaging way, the game is bad. it will turn out bad no matter how good the graphics are. it shows that the designer has no clue what they want from this game and even if they have a weird abstract idea of it in their head, there's no way it will translate well enough to become a feasibly fun project.
if you, as a developer of any product, don't understand exactly what and how the product is going to do and work or what new stuff it's going to provide that other products don't, you need to loving stop everything you're doing and hit up the chalkboard again. proceeding down that line of development is the equivalent of building a house of cards on a rubber fitness ball. not only will it have absolutely no foundation or direction, but any changes made during development will destroy the entire project. if by some miracle you finish, you'll be left with a lopsided house of cards so poorly built that it could only be completed with glue and duct tape. and it'll show. everyone who sees it will immediately recognize that the house was built on impulse with absolutely no planning whatsoever. for a real actual example of this house of cards, see hunt down the freeman
from there you could argue: this game is just a pet project. its not meant to be played, its just a test. why are you judging it so harshly?
simpler answer: dont post your stuff in public unless you are prepared for any and all criticism. the moment it touches a public forum you're disclaiming that your game is a private pet project that you're making for your own personal development.
as a last resort you could argue: why are you such a richard?
best answer: eat my ass