I mean, I don't think that Steam sells any physical media either.

Granted, Steam isn't the only place to buy PC games, but I went looking in an earlier thread that was talking about the PS5 physical disc shutdown. I could think of one retailer, Matrix Games

they specialize in milsims

that still sold physical media. It looks like they shut that down last year, had a "last call" for orders for games on physical media.

https://www.matrixgames.com/news/important-update-last-chance-to-purchase-physical-manuals-and-editions-before-march-1st

Dear Wargamers,

We want to share an important update with you.

Starting March 1st, 2025, Slitherine will no longer sell physical game manuals or physical copies of our games through our website. This marks the end of an era, and we understand how much these editions have meant to many of you over the years.

There is a trend away from Physical purchases to digital, and a decreasing number of new PC’s even have DVD drives and very few laptops meaning the potential market has been shrinking for years. This, combined with increasing delivery costs, environmental awareness, and more red tape on international deliveries, all combine to make it unviable.

For those who appreciate the tactile experience of a physical manual or a boxed edition, this is your final chance to secure a piece of wargaming history. You have until February 28th, 2025, to purchase from the remaining stock, after which these products will no longer be available.

Physical Editions Still Available

Here’s the full list of titles still available in physical format:

• Combat Mission: Battle For Normandy
• Combat Mission: Black Sea
• Combat Mission: Cold War 
• Combat Mission: Final Blitzkrieg
• Combat Mission: Fortress Italy
• Combat Mission: Red Thunder
• Combat Mission: Shock Force 2
• Command: Modern Operations
• Decisive Campaigns: Barbarossa
• Flashpoint Campaigns: Southern Storm
• Gary Grigsby's War in the East 2
• Gary Grigsby's War in the West
• Panzer Corps 2
• Rule the Waves 3
• Strategic Command WWII: War in Europe
• Strategic Command WWII: World at War
• Strategic Command: American Civil War
• Strategic Command: World War I
• The Operational Art of War IV
• War in the Pacific: Admiral's Edition

If you’ve been considering adding one of these titles to your collection, this is the time. Stocks are limited, and once they’re gone, they’re gone for good.

We thank you for your unwavering support and passion for wargaming. Together, we’ve kept the spirit of strategy alive, and we look forward to continuing this journey with you in the digital age.

And that wasn't a large portion of their library

like, you couldn't get physical-media versions of most of their games even then.