Ironically, Duel Links is one of the most generous digital card games if you know how to farm efficiently. While you cannot get "unlimited," you can get thousands of gems a month.
Despite the server-side reality, several types of mods circulate on YouTube, Discord, and sketchy APK websites. Here is what they actually do: Yugioh Duel Links Mod Unlimited Gems
Go to "Life" -> "Lifetime Missions." These reward gems for cumulative actions: Ironically, Duel Links is one of the most