every wired connection is exclusive to the device and full duplex.
That doesn't seem quite right in reality, since the moment you have multiple devices connected to one switch and both sending data to the router, they're sharing the connection. Switches can handle multiple connections at the same time way better than an AP, being able to receive from multiple devices at once, but the bandwidth will ultimately still be shared between the devices.
I don't think the line is that fine in that case, considering all random mechanics in Balatro give ephemeral rewards that only last until the end of a run, which is an isolated instance of a game with limited playtime, those mechanics cannot be paid for with real money, the resulting rewards cannot be sold for real money or traded with other players, and generally cannot affect any other players in any way, not even visually through cosmetics.
As far as I know, Balatro is only really being targeted because it's stylized after poker, with the enforcement having no actual understanding of what the gameplay looks like.
I think at bigger risk from actual laws would be MMORPGs where you can get random loot drops from enemies/chests, and those also tend to have markets where people grind valuable drops and use in-game trading to transfer them to other players in exchange for real money.