works perfectly fine for physical too, it basically installs the digital version of the game but just makes sure the disc is inserted while you play. Its a really good idea to grab the digital version though when it goes on sale, no reason not to since discs eventually fail.
They were always hard to get. Demand spiked a lot with Halo coming out now.Smart of them, but a bit late. Are Series X still hard to get? Because this almost looks desperate to do it now.