So you want your game to appeal to users who buy and thoroughly play lots of games (and likely would snap up yours anyways if it was in the same genre) while also discouraging users who are new to the market?

If requiring you to do stuff for some reward instead of just giving it to you is "discouraging users" in your mind, I think you've missed the point of many games.

Maybe they're all games you made, maybe they're all games built in a community, maybe it's a fan made extension of another game. Those all have reasons you may want to add access to something based on data from another game. Perhaps it's a core mechanic, where puzzles are only solvable by completing tasks in other games. Perhaps it's just letting you play as Guybrush Threepwood if you've played the first Monkey Island.

It doesn't have to be all within games. Gated access to communities perhaps (a speedrunning discord if you've got a certain achievement).

The ingenuity of game devs never ceases to surprise me, and sharing data between programs is fundamental to lots of interesting systems so the idea that sharable data between games provides no utility is odd to me.

I don't dislike this sort of unlock system - I think Assassin's Creed Odyssey made a thing of it by letting, for instance, you crew your galley with Enzio wannabes if you'd played through AC2. However, the utility is pretty low and I'd imagine you end up sinking more dev time into the endevour than you're going to reap.

I've worked in the gaming industry. Margins are incredibly tight and the timetables are usually extremely brutal. It'll take time to support different character models and swappable cosmetics have, on multiple occasions, resulted in game exploits. One of the early notable ones was Oddjob in Goldeneye[1] but you also often see clipping bugs where tall characters might clip through no pass boundaries and either insta-kill themselves or find a way to get out of bounds. These things have costs.

1. https://www.eurogamer.net/articles/2018-08-23-21-years-after...