I think you should think about as another tool you can use to make your modding experience better.
It allows for managing load order and now the Vortex plugin supports it so in essence you install the DLC on steam/gog and you don't need to bother with anything really just use Vortex.
I would say the reasons to use it:
- It's maintained properly by CDPR so you can expect it to work out of the box with every update.
- You can play without mods with 1 click if something breaks
- Load order
- Doesn't affect CET etc. because they play along nicely
- Has a cool name
- REDmod sound mods for example only work with REDmod which you can do with CET etc but it is much cleaner this way.

So all in all, it's a tool and you have to decide for yourself how you utilize it