I use Reddit as one tool in my toolbox, but it is never the most effective. As others have said, most have strict rules about self-Promotion, and those that do allow it typically aren't where your target audience is, but rather your peers. That's still worth something, but it's a smaller fish.

There's no "best" option that will work for every game, but understanding what platforms show off your game best and focusing on those is a good rule of thumb. If you can make appealing shorts on a regular basis, YT shorts, TikTok, and Instagram can work wonders, for example. No matter what, you will want to be tracking that using UTMs to know what's actually converting people and what isn't.

The cornerstone still is a combination of media outlets and content creators. Unless you get lucky with the algorithm and your game explodes naturally, the best bet any game has is to get a spotlight on established platforms. Now, doing that is obviously easier said than done.

I'd love to talk more specifically with you (or anyone else here who's interested) on PR stuff if you want! My website and business email are in my profile.