I think having places to play video games with others is a welcome addition.
If it were up to me, I wouldn't charge anything to let people come in and play. The more people frequenting the building, the better off you are. More people = more business.
Like someone said, have a bunch of TVs hooked up. You have no problem acquiring used consoles, use those units to connect to the TVs.
Start selling candy, drinks, etc. This stuff has high profit margins.
The only issue would be reconfiguring existing stores to accommodate the change.
Get rid of used and new game sections completely. Keep everything behind the counter. Use a digital interface to push these products; there can be a couple displays in store that you search the inventory of the store for which game you want.
Ditch the merchandising setups that push trash products.
Remove the demo kiosks that let you try out PS4, Xbox One and Switch stuff.
Instead of used game racks, there's TVs on the wall. Instead of merchandising racks in the middle of the floor, there's couches. Instead of demo kiosks, there's candy/soda/popcorn etc to purchase.
There's a Switch section, an Xbox section, and a PlayStation section. Each section has TV, couch, console and a variety of games available to play. Considering you have loads of used games on hand, there's no point keeping them barred off. Let people play them. It's not like they are new games; their value isn't being decreased by having them played in store. You can even possibly charge cheap rental fees on them (and they aren't even leaving the store); let's say it costs $2 to switch to a different game.
Large TVs are extremely cheap these days. Mount 70inch+ TVs on the walls. This gives an experience that not everyone can enjoy; many homes don't have room for TVs this size.
Considering anyone can go to Walmart/Target/Best Buy and get the same exact experience that GameStop is offering (aside from a used game selection with marginally reduced prices; many times the used games are more expensive than new copies elsewhere if you do your research), obviously there needs to be a fundamental business change. You aren't offering people anything different than large retail stores.
If you change the stores into something where people can come hang out, play some games, buy some junk food and socialize, perhaps that will increase your customer base.
