This would be a big plus for me too.
I made a burger icon (basically two lines) and was looking for the output to be something like:
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 36 36">
<g fill="none" stroke="#000">
<line y1="12.5" x2="36" y2="12.5"/>
<line y1="23.5" x2="36" y2="23.5"/>
</g>
</svg>
Here's the output from Affinity (minus the extra tags/properties I would strip out anyway):
<svg viewBox="0 0 36 36" xmlns="http://www.w3.org/2000/svg">
<rect id="Burger" x="0" y="0" width="36" height="36" style="fill:none;"/>
<clipPath id="_clip1">
<rect id="Burger1" serif:id="Burger" x="0" y="0" width="36" height="36"/>
</clipPath>
<g clip-path="url(#_clip1)">
<g transform="matrix(1,0,0,1,3,12.5)">
<path d="M0,0L30,0" style="fill:none;fill-rule:nonzero;stroke:black;stroke-width:2px;"/>
</g>
<g transform="matrix(1,0,0,1,3,23.5)">
<path d="M0,0L30,0" style="fill:none;fill-rule:nonzero;stroke:black;stroke-width:2px;"/>
</g>
</g>
</svg>
Just way more complex than it needs to be. Would love to see an improvement on this.