Moreover, JPEG XL includes several features that help transition from the legacy JPEG coding format. Existing JPEG files can be losslessly transcoded to JPEG XL files, significantly reducing their size (Fig. 1). These can be reconstructed to the exact same JPEG file, ensuring backward compatibility with legacy applications. Both transcoding and reconstruction are computationally efficient. Migrating to JPEG XL reduces storage costs because servers can store a single JPEG XL file to serve both JPEG and JPEG XL clients. This provides a smooth transition path from legacy JPEG platforms to the modern JPEG XL.

https://ds.jpeg.org/whitepapers/jpeg-xl-whitepaper.pdf

Up to 46% compared to PNG is more than a bit extra. It’s also supports both loseless and lossy compression and supports backwards compatability between legacy JPEG. Among many other modern features.

And PNG is so old that it lacks basic modern features like HDR support.

The only competition to JPEG-XL is AVIF. Though both likely to coexist as they have different strenghts.

Good luck.

The cable is not available on Amazon yet, so you’ll need to buy it directly from the Japanese site and find a way to have it shipped.