Presentation attributes in SVG 2

SVG has a concept of presentation attributes. Essentially, those are style properties, like fill, that can be set via CSS, a style attribute and as a regular XML attribute. Meaning that all of the following examples are functionally identical:

<style>
    #rect1 { fill:green }
</style>
<rect id="rect1"/>

<rect style="fill:green"/>

<rect fill="green"/>

SVG 2 changed this behavior and all new presentation attributes are no longer allowed to be used as regular XML attributes. So you can write style="mix-blend-mode:screen", but not mix-blend-mode="screen".

I have no idea why it was done, but it's a really annoying change. All SVG 2 presentation attributes had to be skipped during XML attributes parsing now. And an SVG writing library is essentially forced to use style everywhere, which makes a resulting SVG harder to read and parse.