Comment 2 for bug 1863625

This would work in the general case, but not always. xdg-open special-cases some well-known desktop environment (e.g. GNOME, KDE, XFCE), and for those it would work. But other more obscure DEs may not expose what xdg-open needs to handle mailto: links, which I guess is why xdg-email exists in the first place. There are details in the chromium bug I shared in the description.

So symlinking xdg-open to xdg-email would definitely be an improvement over the existing situation, but not a complete solution.