Does a streamer do anything to the data that Tidal provides?


I have been streaming Tidal to my HiFi for the past 4 years with a streamer and a DAC connected to my amplifier (Raumfeld streamer to Musical Fidelity DAC and also Musical Fidelity Amp). I also have an all-in-one system for my summer house (Naim Muso Qb). So, I know the basics and I am only interested in streaming from Tidal.

What I struggle to understand is, what the streamer does apart from transporting the digital signal and therefore why it could make sense to invest in an expensive streamer.

I understand what Digital to Analogue Conversion does and that it makes sense to ensure a good quality, but isn't the streamer just a transporter of data? Does the streamer do anything to the data that Tidal delivers apart from receiving them and sending them to the DAC? 

Thanks in advance, Michael 
mtraesbo
Many thanks for a lot of inspiring responses. I must admit, though, that I still do not understand, how a streamer can enhance the bitstream.
 
If the streamer is a transporter that connects the music sources with the DAC then how can it make the output any better than the input? 

I understand that if the input is provided in higher format than a streamer can manage, then a better streamer can do a better job. But if a cheap streamer can manage the input stream from say Tidal and provide it to the DAC bitperfect, then the job is done - isn't it? 
You are absolutely right. It cannot in any way improve the sound. If it is working properly what comes in will come out in exactly the same bitperfect shape and form.
Of course, if it also includes a DAC (quite a few do) that DAC may influence the sound. But the streamer part is neutral.
Many thanks, Willemj, 

So if my aim is to increase the sound quality of my setup (only listening to Tidal HiFi through Raumfeld streamer, Musical Fidelity DAC and Musical Fidelity amp) then I should start by getting a better DAC as the current streamer does 24 bit/192 kHz, right? 
I doubt a new DAC will give much better sound quality, if any. If you want better sound I would look at the speakers, as they are responsible for by far the largest part of sound quality (but I don't know what speakers you have). Do you have enough amplifier power (Musical Fidelity has many amplifiers)? What size is the room and does it have a hard acoustic, or not?
@willemj I need your advice re. Chromecast, again!!! It is now connected thru mini-Toslink to an external DAC (Wadia 781i) and I cast Tidal using iPad. I noticed only today that when streaming I can change volume with iPad volume control. It seems that SQ is at its best when volume on iPad set at max, or is it my imagination?!? Wadia has its own digital volume control and they promise that if you stay above 75% then SQ is not getting affected. Could find nothing about this from Chrome.