My phone updated a couple days ago, i got in and messed with the settings this morning. I dont know if you're on verizon and got that update too, but if you set the Hard Press Home key setting to on and to level 5 it seems to completely disable it. Which to me seems to go against what it says it does, but at level 5 it doesnt work at all, which to me has disabled it in all my games. On my side it seems fixed so far and something else that I dont like nor use is now broken and i'm fine with that.
In the end, there needs to be a setting to set soft home button to off when navigation bar is hidden, there are more drawbacks to having that feature than it has benefits. The hidden navigation bar with a swip up to show is something i'm used to and its fine and gives me plenty of access to the home button.
Or how about map the bixby button to hide and unhide the navigation bar so we dont open it by accident.