The difficulty, obviously, is in finding out which decks are good and which aren't. But that's a discoverability problem that is hard to avoid since people are just going to have different requirements and preferences. You can try going by the ratings or check language learning subreddits for recommendations, but ultimately it's up to you to try out decks and see if they work for you. If you just use Duolingo instead, you're arguably not using a better deck, just one with better marketing.
https://ankiweb.net/shared/decks
The difficulty, obviously, is in finding out which decks are good and which aren't. But that's a discoverability problem that is hard to avoid since people are just going to have different requirements and preferences. You can try going by the ratings or check language learning subreddits for recommendations, but ultimately it's up to you to try out decks and see if they work for you. If you just use Duolingo instead, you're arguably not using a better deck, just one with better marketing.