Being a game creator and couldn't make the dream game isn't necessarily something bad as making a great game always have a strong team behind. And after reading all the details of how would you like to be the game, thought in advance, just shows how calculated and dedicated you are to this passion.
To be honest I've had this passion too, even from my youth and I even thought about becoming a game creator one day because playing so many games you get this feeling that you could also come out with a great game that will be a success for gamers, but then again you don't know from where to start or if you could do it by your own so I believe that sharing your ideas with a very experienced team would be both a successful for you but also for them and a nice collaboration that will end up in an amazing game.
Now talking about the description of the games. I do believe that they are really important as depending on what you are reading or seeing if we are thinking about a trailer, depends if you want to try that game out or not. And I do think that you have to be very creative and know how to transmit with the people the real story of the game so they could also feel it, but then there are lots of games that are taking advance of this fact and create false hopes to the gamers that are all faced when trying the game, resulting in many bad reviews in a short time (I remember many AAA titles when receiving rough impressions on steam).
These being said, I really hope one day I will play the dream game you have and totally enjoy it! I'm have no doubt about that 😊
I think the thing that drives me as a creator is a sense of realism. I may not make my dream game, but I can set the foundations for it, moving the industry in that direction and encouraging others to move in a way that leads to it.
Really, the thing that I'd suggest if you want to be a game creator is to not put it off and start doing a little designing every day. Start with a simple board game or a tiny game in GameMaker or another simple tool and get a feel for it. Move on to whatever feels right to you, and don't forget to follow your passions. Eventually you can learn to finish stuff (it took me a decade), but you can't get started unless you start doing.
The real thing to remember when talking about games is that you don't necessarily have the same vocabulary going on at the designer and player level. A lot of terms that are really important to a developer (things like "procedural", which has come to mean "random" in the eyes of consumers due to no small amount of misuse and ineptitude) don't really mean a whole lot to outsiders, and they don't market well. Large companies try to make their games marketable, but do so by using methods that don't actually reflect a good product (No Man's Sky launched with billions of unique, but not distinct, planets). It's a question of whether designers stick to principles and reality, or if they overpromise and try to spin things that don't really exist into their core selling point.
I couldn't say it better than you did, and that example with the No Man's Sky is perfect. You are so damn right! :)