Howdy!
I'm still getting the hang of the message system, so I may mess up quotes and suchlike.
I did a quick check to see if what I remembered from botany (and all y'all Master Gardeners and Botany profs, please be nice!) still counted.
It seems to.
From website :
https://gardenerspath.com/plants/vegetables/save-kale-seeds/
And as they fade from green to beige, you need to act quickly to preserve the ripe fruit. Waiting too long can result in dry pods bursting open and dispersing their cache. as they fade from green to beige, you need to act quickly to preserve the ripe fruit. Waiting too long can result in dry pods bursting open and dispersing their cache.
So, depending on where your kale's seedpods are on the green to brown continuum, I don't think your kale needs it's leaves anymore. Have at and have fun!
As to what is eating it?
A quick "5 click search" turns up sowbugs/pillbugs; snails; slugs; millipedes; spider mites; and Japanese beetles. As the damage started low, I'd probably start with the slugs, snails, and sowbugs/pillbugs or just write the leaves off.
Good luck!