https://news.xbox.com/en-us/2020/05/28/xbox-series-x-next-generation-backward-compatibility/
"Gaming leaves an indelible mark on all of us. From the epic stories and universes we experience playing as our favorite heroes, to the heat of intense competition, victory and defeat. Through the shared accomplishments we achieve as a worldwide community, gaming brings us together.
Thousands of developers from across the globe are currently creating the next generation of transformative games, many of which can only be realized through the power and innovation of the Xbox Series X. Led by Halo Infinite, our 15 Xbox Game Studios teams are hard at work creating the biggest and best line up of exclusives in Xbox history. We are incredibly excited to show many of the new games in development for Xbox Series X soon.
Preserving Your Gaming Legacy
As gamers, we also know how important it is to preserve and respect our gaming legacies. Your favorite games and franchises, your progression and achievements, and the friendships and communities you create through gaming should all move with you across generations. Not only that, your favorite gaming accessories and peripherals should also move forward with you as well....
Compatibility Journey
...Through a tremendous amount of hard work, technical innovation, and partnership with the industry’s leading creators we were not only able to bring more than 500 Xbox 360 games to Xbox One, we were able to go back even further into the archives and resurrect some of your favorite franchises from the original Xbox. The very same team who created new innovative ways to preserve and enhance your existing catalog of games on Xbox One is the same team pushing the envelope again with Xbox Series X....
All Games Play Better on Xbox Series X
Not only should gamers be able to play all of these games from the past, but they should play better than ever before. Backwards compatible games run natively on the Xbox Series X hardware, running with the full power of the CPU, GPU and the SSD. No boost mode, no downclocking, the full power of the Xbox Series X for each and every backward compatible game. This means that all titles run at the peak performance that they were originally designed for, many times even higher performance than the games saw on their original launch platform, resulting in higher and more steady framerates and rendering at their maximum resolution and visual quality....
Advancing the State of the Art of Game Preservation
...With all of the additional power and advancements of the Xbox Series X, the compatibility team now has a veritable playground of new capabilities to innovate and push the limits of game preservation and enhancement. The compatibility team has invented brand new techniques that enable even more titles to run at higher resolutions and image quality while still respecting the artistic intent and vision of the original creators. We are also creating whole new classes of innovations including the ability to double the frame rate of a select set of titles from 30 fps to 60 fps or 60 fps to 120 fps..."
I left out most of the article, but highlighted some of the key features the Series X has to offer. Some other fun tidbits include automatically adding HDR to games including X360 and original XBox games, and quick resume working with BC games. It shows how dedicated the Xbox team is to preserving everyone's legacy of games they own.
