Well I wouldn't say it's evil, just that there may be advantages to other connections in some systems, and a necessity in others. The Bermuda Triangle weirdness I mentioned earlier was a MacBook Pro running wireless and on battery that made a horrendous noise connected to an Arcam irDac via usb, music didn't even have to be playing. Sounded like a ground loop on steroids. How is that even possible? But an optical cable made the problem go away.
@carlsbad In my case the only streamer output is usb, so I had no choice but to try a converter if I was going to use a different input on the dac. Ideally it would have been toslink out > fiber > toslink in. I do however think there is potential with some of these decrapifiers, reclockers or converters. In theory a flawed signal goes in and a newly minted "perfect" signal goes out. You could very well be right though.
My only point is, I like many audiophiles, tend to snub our noses at toslink. What I'm hearing now has really changed my opinion of that. Honestly I didn't think it was capable of this high a level of performance. Most streamers and dacs already have the connections, if yours does I'd give it a try. Digital audio is like a box of chocolates so maybe you'll like it in your system, maybe you won't. Mine is staying.