I haven’t been able to get good results from ImageMagick in this instance, but Inkscape does a nice job of scaling an SVG on Linux and Windows:
# Inkscape v1.0+
inkscape -w 1024 -h 1024 input.svg -o output.png
# Inkscape older than v1.0
inkscape -z -w 1024 -h 1024 input.svg -e output.png
Note that you can omit one of the width/height parameters to have the other parameter scaled automatically based on the input image dimensions.
Here’s the result of scaling a 16×16 SVG to a 200×200 PNG using this command: