Grooming standards change with changes in society. In the 60's, airlines forced stewardesses to wear girdles. In the 80s, it was generally considered inappropriate for women to wear trousers in the workplace. Both would not fly today because society's expectations have changed and companies have to keep up with the times.
Whether you like it or not, tattoos (of which I have none) have gone mainstream in modern culture and are no longer reserved for the lower classes. Tattoo bans made sense when customer expectations on professional image and attire dictated as such, but times have changed, and I'd venture to guess on any given day there are plenty of Upper Class pax with visible tattoos. With companies having to compete more than ever before for talent, relaxing this rule makes sense to me. I hardly think tattoos make or break one's ability to keep pax safe or to provide good service.
I think VS struck a fair middle ground with allowing some but not all tattoos. Who knows, though, maybe in 20 years neck tattoos will be the norm? I've seen stranger things happen in my lifetime.