Any kind of conversion will cause degradation of the contents of an audio file. Even for post processing in a DAW, my personal belief (as a certified sound engineer) is that it is better to stay within the native sampling frequency/bit rate of any track. With 44.1 being the CD-standard, it is safe to say that this quality is high enough for the most critical listener on a high end hifi system. Us DJ’s at not always great PA’s, at high volume levels and with drinking customers who are not there to “listen” to the music, it is a total non-issue. Again, in my humble opinion.
Sidestep: Only if you record in 48K (and if I know I am gonna end up with CD-quality anyway, I’ll actually opt for a 44.1K recording setting) is it worth processing in that rate. Frankly, if you record, doing so at 88.2K makes way more sense. Down-scaling would be a precise 2:1 ratio, relatively easy to calculate. As opposed to recording at 96K, which brings the ratio to approx. 2.18:1. Clear how that requires a lot more calculating and “guessing”.
If you go from sampling 44.1K times per second and upscale to 48K (only a relevant rate because the DVD boys decided they wanted something else for DVD audio), the computer will try to insert the missing bits. At best it’s an educated guess based on the previous and next values and the steepness of the waveform. So, if you do post-production in a DAW, you are manipulating stuff that wasn’t really there to begin with. When you then down-scale to 44.1K, the computer needs to take out bits here and there to make it “fit” again. You can see how that wouldn’t enhance the quality, it would sooner be a degradation.
End of the day, for any and all DJ purposes (including publishing your work on soundcloud etx, streaming/broadcasting it, distributing it on CD - should you still be inclined to do that)), CD-quality 44.1K is fine. Just stick with it throughout your recording to mastering process and you’ll be absolutely fine.