There are a couple of YouTube videos on the GDC YouTube channel that discusses Discord and how to use it to create a dedicated community before game release. One is called Game Discoverability Day: Building a Community for Your Game from Scratch presented by Mike Rose.
But, I think it depends on the goal of the creator and the game. If the goal is to create a dedicated fanbase for the game that's going to be excited about buying the game upon release, Discord might be a good option.
If you're more concerned about getting your game discovered by more people, I'm not sure if Discord is an effective place to do that. But, I haven't used Discord for the purpose of getting something discovered. I use Discord to motivate myself to work on projects or to communicate with friends to play multiplayer games.
I took a look at your page for 10 Days to Jupiter. Your page is organized in a professional way. Based on the images, the game looks polished. I love the last picture posted with the tree dressed in a jacket and sunglasses.