Better compression can also mean a new set of filter methods or a new interlacing algorithm. But yeah, any of them would cause an instant incompatibility. As noted in the relevant issue [1], we will need a new media type at the very least.
[1] https://github.com/w3c/png/issues/39#issuecomment-2674690324
I am hopeful whatever better compression doesn't end up multiplying memory requirements, or increase burden on cpu, especially on decompression.
Now, PNG datatype for AmigaOS will need upgrading.
We would need a new media type. But the actual new features don't need one, because the news don't break compatibility.
https://svgees.us/blog/img/revoy-cICP-bt.2020.png uses the new colour space. If your software and monitor can handle it, you see better colour than I, otherwise, you see what I see.