They really do.Boss makes a great guitar cord
I buy the cheapest off of Amazon lol Ive had some higher end ones and outside of durability, I don't notice a difference.
I'm sure there is a happy medium
Oddly enough I never noticed a difference in guitar cables until one day when I was playing my Rickenbacker 4001 bass through a cheap cable and thought it sounded dull, I switched to a higher quality cable (don't remember the brand) and I noticed the high end come alive. After that I bought a few high end cables, but I came to the conclusion that extremely high end cables are not really needed, I just avoid the really cheep ones. IMHO