As mentioned in the comments, you’re using the wrong method to check how the SVGs scale.

The zoom slider in the game window does not re-render your scene at a higher resolution.

It takes your existing render at a fixed resolution and draws each pixel larger.

So no content, not SVGs, not SDFs or other mathematically computed effects, nothing will get more detailed or smoother as you zoom in, and that’s the deliberate behaviour of this zoom feature.

The reason for this is so that you can more easily examine things like aliasing artifacts without having to peer uncomfortably close at your screen, or take screenshots to enlarge in another program, or use an extra magnifier app hovering over the Unity window. It integrates this “let me see those exact pixels, but bigger” workflow into the editor interface itself.

To see how your game would look at a different resolution, keep the zoom slider at 1x and change the resolution drop-down box in the top left corner of the game view. This changes the size of the virtual screen the game is being rendered into, prior to any pixel zooming. So SVGs, SDFs, and other shader effects will be rendered smoother as you increase the resolution here. This rendering will faithfully match what you would actually see on a device that has more (or fewer) screen pixels to draw on.