Dark mode is tough to implement, you have to re-design the whole page and it doesn't render well in old type screens (Thinkpad Matte, LCD). To properly view darkmode you need Retina like display.
The strain part is the bright white light, why not just modify that? Turn the white to grey. Renders well on all screens, no need to redesign the page. Plus less strain on the eyes.
Wouldn't that be a better alternative than darkmode?
For what little it's worth I got pushed into VS editor (which shouldn't have taken pushing, it's a great environment) defaulting to darkmode and on less-than-Retina-grade panels I'm enjoying it