... thoughts on Taylor Swift's REPUTATION CD...

The harshness in her voice (and other artists today) is mostly due to the use of effects specifically Autotune. These pop and rap recordings are not using a sine wave to organically correct pitch, a square wave is created and the gain is pushed high into the vocals. Next add the loudness part with the use of limiting and compression and you have buzzing, electronic sounding vocals.
It's the style of pop music today.

And then each radio station adds a fair amount of compression. And for streaming (iTunes) the original files have the data compressed into a low-res version of the song.
 

For sibilant voices engineers use filters and a mild amount of compression. This is standard practice. 
There may be sibilance thru your speakers due to tipped-up highs from the mix and/or mastering. 

gosta: NOT ON TOPIC - but give a listen to The Eagles 2-disc THE VERY BEST OF, on your 15" woofer Westlakes and APCs

disc 2: track #3 - Victim of Love
             track #13 - Those Shoes

Listen to the beginnings of both; I used to blast these 2 tunes with my mid-50s University S6 (3-way with 15" woofer) - and THEY ROCK !!!
I still use them when testing others' speakers and systems...

Regarding the vocal mushing on 'REPUTATION': it has to be an engineering thing. I am trying to recall clean vocals - I remember some nice stuff on The Dixie Chicks CDs...

... according to what lowrider57 has stated: WITH RECORDED MUSIC - we are never going to truly hear what an/any artist really sounds like...

I know that the days of hearing Harry Chapin with 57 other people in a college cafeteria are gone - real sound is harder and harder to find - but it is a depressing thought that we really don't know what an artist sounds like. Reminds me: My son and I got a reality check when we heard HOOBISTANK live- so so disappointing - AND NOTHING LIKE THE MUSIC WE LISTEN TO ON CD!

Agree. In my opinion nothing that records, analog or digital, is a true representation of reality. It is, almost by definition, a facsimile. Usually in photography this is acknowledged and the goal is not to say: This is the subject as it is but to say this is the subject as I (the photographer) wish you to see it. I have no problem with that in photography or recorded music. In that regard my limited hi-fi pursuit is not a search for what is closest to reality but what is well presented. I think production and recording are nearly as important as the music itself. They can't stand alone but they can compliment and enhance each other.

I'll have to say that The Struts, at least in the small venue I saw them in, got the vocals just right from a live standpoint in that he sounds much a he does on his CDs (even with their fairly low quality). I was frankly astonished how clear and precise his vocal were especially given the raw nature of the performance and the overall (ear damaging) volume. The sound personnel did a fine job and the singer is very consistent.