The sound of fingers on strings can be irritating, I agree. Players with superlative technique, (and Martin Simpson is the only one I can think of in the folk idiom) are able to record without any string noise whatsoever.

But some syles of music do require the occasional glissando and string noise is an inevitable by-peoduct of the technique, especially when using new strings. Lubricating the strings with Fast-Fret or WD40 can help, however.

Murray