There are a couple of requests for improvements to SVG export, which is sorely needed. One important aspect of this is accessibility.

SVG use is increasing, and accessibility requirements are being mandated in jurisdictions around the globe.

There will be a growing need for people to produce accessible SVG files.

This calls for supporting ARIA roles states and properties, and some way to indicate tabindex.

A number of constraints can be imagined to prevent people doing the wrong thing (e.g. if you put tabindex=0 on a non-operable element), but the basic functionality is far more basic.

Select object.
Open aria palette.
Add / edit / remove role (e.g. checkbox)
Add / edit / remove state (e.g. aria-checked) and default value for that state.
Add / edit / remove property (e.g. aria-label) and default value
Checkbox for "focusable" (sets tabindex="0") if false, no tabindex attribute and the next checkbox is greyed-out).
Checkbox for "programmatic" (sets tabindex="-1")
Export SVG
Result: Aria roles, states, properties and tabindex attributes present and correct in the corresponding SVG elements.