There is no public database or universal record of an individual's personal gaming preferences. Unless "Cameron" is a public figure (like a streamer or esports pro) who has shared this information publicly, the only way to know their favorite Xbox game is to ask them directly or observe their activity.
Simply ask: "Hey Cameron, what's your favorite game on Xbox right now?" This is the fastest and most accurate approach.
If you are connected on the Xbox network:
If their privacy settings allow, their activity feed shows recently played games, unlocked achievements, and clips/screenshots shared.
If Cameron streams or creates content, check their Twitch, YouTube, or TikTok for frequently played titles.
Friends who game with Cameron regularly will likely know their go-to titles.
Xbox privacy settings allow users to hide their game history, playtime, and activity feed from everyone, friends only, or specific people. If their profile appears sparse, they likely have strict privacy settings enabled.
Summary: Without direct access to Cameron's account or public statements, an AI or third party cannot retrieve this private information.