I've used embedded SVG images in CSS encoded as base64, and I'm not ashamed. In general, I really wish I could apply page styles and CSS3 variables to the internal CSS of SVG files. I'm sure there's a good reason why this context isn't shared, but it would be cool and useful to dynamically change the style of SVG files.
If I'm hand coding a page or writing a stylesheet, it's convenient to be able to embed things. Often, I'll embed a style tag until it grows large enough to be worthy of its own file. The same goes for scripts; it's useful to have the option if you're quickly prototyping something.
You CAN target ids in svgs though? And apply fill etc by css
Not in all situations. I'm pretty sure I can't do it when the SVG file is applied as a background image.
I don't know if I remember seeing this site before -- it appears to be an advent calendar of web performance tips? Good stuff.
Yup, it’s web performance advent calendar in its 17th edition. I’m the maintainer, AMA. Also still accepting contributions for this year.