It's visually equivalent to a u, so without vowels it's still possible to get "fvck", for example.

The Romans wovld approve of svch a scheme.

How would the Romans have pronounced 'approve', though?

I suppose it's about the use of 'v' instead of 'u' in the F word

imagine the phrase "see you later" was offensive, or perhaps its abbreviation "cu"

the combo "cv" could then become problematic.