There is another aspect of SVGs
They are really text files. And so can be (could have been) uploaded to the HIVE (steem) block chain in total.

example of a rectangle

<svg width="400" height="110">
<rect width="300" height="100" style="fill:rgb(0,0,255);stroke-width:3;stroke:rgb(0,0,0)" />
</svg>

The thing with SVGs is that every entity is a line of text.
So, i can make a bar graph in a few K, but if you are doing a fuzzy animal, every tuft is a line.