Carys is "KA-riss" to me. When I first came across it, it was "KA-riss" to me, not "CAIR-iss". But it's like
Cara were a lot of Americans seem to go for the very 'r' sounding "CAIR-ra", when it's always been "CAH-ra" to me and all the Caras I have ever met.
I have never considered it as a plural form of
Cary to get "carries", but then I have never met or come across a
Cary.
Stereotype: It's like the trendy Welsh name to me. I would go
Angharad or Anchoret over
Carys.
If kids want to make up names they will. I would not discard a name just because of names that 'might' be though up.