This is the most relevant subreddit you’ll find for general gacha content/news (unfortunately it’ll be quite empty until gacha catches on in the west).

As for Discord, there aren’t any “go-to” servers, so your best chance is finding the server of a streamer or content creator that covers the game you’re interested in. Most servers with a sizable community are full of gacha discussion, and many streamers who play gacha usually keep up with multiple gachas. Chances are you’ll find someone way more addicted than you are.

A handful of redditors provide great insight into new gacha in this sub, but sadly a lot of games that are discussed aren’t translated to english. This isn’t their fault; there just aren’t that many gacha games available to the typical consumer in the west.

tl;dr : Follow the subreddit/discord of the specific gacha game you’re interested in. This sub will gain traction once the western audience gets addicted to gacha games.