I have had plenty of game ideas in my head that I know could never become a reality since I ain't got the skills or money to make them happen.
One idea is essentially a game for the Luanti engine where it's pretty much you crash-land on Earth, maybe a thousand or so years into the future as someone meant to see how Earth is and if it's habitable again. It would play like one of those quest based mod packs for m*necraft. In this one, you'd essentially be dealing with resource shortages and fighting mainly just robots and whatever very sparse mutated animal life is left on the planet. Throughout the game you'd find different crest like things that would give you various animal based powers. Goal would be collect them all and beat all the bosses.
Another idea I've had is essentially a clone of the Ankama chess autobattler style game Krosmaga. In both games you'd select a character followed by your deck and fight against either a CPU or another player. Instead of followers of the deities in Krosmaga, you'd be taking the role of different anthro animal tribes. Biggest reason I'd wanna make that is so you avoid having to constantly be connected to the Internet just to play it, like you have to do with Krosmaga. Also to add features that should already be a thing in Krosmaga (being able to choose to battle your friend by connecting to them directly instead of the random player matchmaking they do in Krosmaga).