My opinions:
The dealer wants to sell you the dCS.
I would not buy a digital product whose manufacturer has abandoned the entire category. Check the Web; see if people are having complaints about support. I’ve seen a few.
I have not heard every streamer, but I’d rather have an Auralic Aries G1 or G2.1 than a discontinued dCS. I am very familiar with the G1 and think it’s excellent, both in sound quality and in features. It has more of a future than the dCS -- Auralic has offered trade-in discounts, and they continually improve the product and sometimes even add features through free firmware updates.
If you are not using an Auralic G2.x DAC, it's unclear whether the Aries G2.x offers any improvement over the G1. Other than pride of ownership, of course.
Today, it’s just Qobuz for you. Tomorrow, you might change.
No one (not even you) can guarantee what you’ll be happy with. Besides everything else, there’s some luck involved in making the right choice. Good luck to you!