Adding more opinions from manufactures who endorse and use coreless motors over or picking isolated reviewer opinions does not add nothing to this issue ... IMHO there are so many variables in turntable design and so many varieties that generalizations are not possible, and even then they are due to preferences. We have to look at the whole package before taking a decision.
Are you telling us we should not own, for example, a Micro Seiki 8000 because the motor is not coreless?
BTW, I also own a few top coreless cassette decks- two Nakamichi CR7 and one Revox B215 - a few weeks ago I have been cleaning, checking and listening to them, as I am considering reducing the collection. Sorry, but no comparison is possible with the ultra heavy cored synchronous motor Studer A80 ... But yes, they are really enjoyable!
So, seeing a building consensus among expert engineers adds nothing to the issue? It may not be definitive but it says something because, you know those motors are not cheap and business pushes always for saving money in production. Why use a $1000+ motor when a $50 motor works just as well and it can all be controlled by software?? Technics didn't go coreless now because it saves money...they could have just built the same machine as in the past and put new clothes on it but they instead put in a coreless motor that requires also new software to control. Why? Sales Gimmick? I doubt it. They probably took a clean slate approach and decided that if they were going to do DD then this was the best approach. Business culture can sometimes blind a company and they fall behind their competitors in technology. I think this happened to Technics in the past and why they didn't move to a coreless deisgn back then.
BTW, the vaunted EMTs are not so great as DDs. I haven't heard the idlers but the DDs, while having that typical high torque drive and punch, lack refinement and subtlety.
I am not telling you anything whatsoever about what you should or should not own...however, it is quite possible that replacing a 1970s micro cored motor (if in fact they are cored motors) with a brinkmann sinus stands a good chance of further improving the sound. Old micros sound good as do Brinkmann BDs. I think; however, a Brinkmann BD with their new Sinus drive will sound significantly better (haven't heard one yet). I can tell you for a fact though that the Brinkmann Bardo is a very good sounding DD.
I have heard plenty of big Studer decks (I even live within 1Km of the old Studer company) as they are often seen here in Switzerland. Maybe it is better, I haven't heard them side-by-side...you have a Studer A80?
Mainly though we have compared to other well regarded cassette decks that are not coreless and the coreless ones sound smoother and more natural...just like what I have heard with DDs.