Well tbh as you didn’t create the images it’s not handmade by yourself so yes it’s not Folksy legal so yes Folksy can and do close down shops that don’t comply to their TOC’s.
They don’t even have to let you know in advance.
I can’t see a single image that would suggest you took it yourself unless the ones of the flowers all the others belong to ‘other people’. I’ve done some reverse image searches on a some of you items and they all came up as other peoples photo’s.
If you take you own photo’s then that would be Folksy legal classified as handmade. If Folksy have sent you a warning email it means they are giving you the opportunity to take down your listings, because if they have to close your shop you’ll not be allowed to open another one at a later date.
Folksy is for handmade and craft supplies which can be handmade or commerical craft supplies.
Just restart again with new listings that comply with Folkys TOC’s.