Try being a guitar repairman; you'll see lots of cracks on Martins. I've got a couple in my shop right now; an older but not super vintage 000-18 with the classic pickguard crack from a shrinking pickguard and a newer 000 that has a top crack from living in super dry conditions. We fix 'em, they go back to sounding fine.
Ukes tend to be built much lighter than guitars, and a lot (most?) of the vintage Hawaiian ones were made in a much more humid climate than they wind up in. Hence shrinkage and crackage. We fix 'em, they (mostly) go back to sounding fine.
Take a look at some real vintage violins someday. They often crack. They fix 'em, and they go back to sounding glorious.