Why does the latter fail?

[limaceous-bushwhacker]

ls -p | grep -v / vs lsd -F | grep -v /

Latter fails with exit code 1.

[zwpaper]

lsd -F not indicating one item per line when redirect to grep, please try lsd -F -1

[limaceous-bushwhacker]

Ah, finally! This had me scratching my head. Reckon this is something that needs to be fixed?