That's a worthless video. He's replacing a perfectly fine undamaged glass, not a broken one.

Check out JerryrigEverything's video where he tries to replace a cracked back glass and it goes horribly wrong[1] with the thing shattering and needed to be yanked out in tiny sticky pieces.

IMHO, having the back of your phone made of glass shards is insanely stupid repair cash-grab design, when we have so many durable plastic polymers to choose from. They even make the Glock handgun out of bloody plastic.

https://youtu.be/S_W73ouKtjU?si=V06NCNiGzMKmr1_l&t=375