Are Preamplifier’s Relevant Today or just a Hinderance with Digital Playback ?

DAC is not accurate. DAA is proper. Dijitteral Analog Approximator. Clocking errors and jitter will forever be the distortion that, along with the irritation of odd order harmonics, keeps you forever on the merry-go-round. 
Stereo is an anti-social disaster perched on a little postage stamp in a large room because the rest is just waves and troughs. Put a Khorn in the corner run some tube gear and turntable and let the party roll, everyone gets a seat at the show even the cheap seats are good. George Harrison maintained until the day he died that you never heard Sgt. Peppers until you heard it in mono. 

@georgehifi,
we will have to disagree on that front.  my ears tell me otherwise and it isn't close.  

The existence of digital playback technology in a Music Reproduction System is not in any way, matter, or scope related to the need to a preamplifier in any meaningful, significant, or substantial way.  

+1,00000,000 very clearly said and to the point. clearthink .

I tend to over elaborate too much with technical reasons and it confuses some.

Always best to use as much as possible all of the sources output, for reasons of noise/hum/distortion/colorations regardless of what it is, even phono.

You don’t floor the accelerator on a super car (the source), yet keep your foot on the brake (the preamp) to get to the destination ( the power amp)

Cheers George

This topic, like many, has been spoken about, ad nauseam. But the truth is, having a preamp simply depends on 1 thing......  do you need the added gain, which is system dependent. I have not heard ( in my system ) a preamp at the 10K and above price range, but have heard, and have owned, several under 10 K preamps, that sounds less " clean ", than my top model Luminous Audio passive, being fed by my dacs, into any number of amplifiers I run. Speakers are horns,  over 100db, which makes a huge difference when needing, or not needing, additional gain.