The smaller Spider Plant I have in a hanging SIP is growing new, straight foliage. I think it is happier with the new accomodations just like all the plants.
Curiously, it still has leaves that tend to curl. This one is even growing into a corkscrew!
I've searched for answers to this online and it seems to just be a genetic variation, no cause for concern. Personally I don't really care for the way it looks (probably because the aberration triggers an alarm in my brain: what's wrong with this plant?!) but some people find it charming.