GregT, Chaad, et.al.,
I've not talked directly with Noma-- will do so in the near future. Given my comments above, I know that is sort-of a "huh?"... , but my primary input on the topic is via Ken Wright, and some personal experience.
I'm reluctant to share that input in any detail as it was via a conversation with Ken and I don't know whether or not he intended any portion of that conversation, or all of it, to be confidential or public. And in either case, I most certainly would not want to misrepresent anything that he said.
What I am comfortable saying, because it is publicly known / verifiable, is that Ken has used Noma corks for a meaningful number of years (so there is some "history" for the findings / views). He has had VERY good success / consistency with the closure both for short-term and "longer-term" cellaring of OR Pinot Noir. (That, of course, begs the question as to what is one's definition of "longer-term"... in this case, I'm talking practical experience in the 6 to 8-years from vintage date sort-of timeframe... and I'm not suggesting that is the limit, but rather what has been evaluated).
That said, you are correct that the one notable performance issue is the impact of the closure on the life span of the wine. In this regard, the appropriateness of the closure would be driven by the intended and / or typical consumption timeframe of a particular wine. At the same time, what needs to be stirred into the comparison is the failure and / or negative impact incidence of natural cork. It is a mistake to look at a prospective early-aged wine with a synthetic cork, and compare it to the aging of natural cork... while assuming that every bottle of natural cork wine will age perfectly. Put another way, I dumped a bottle of 1990 Ceretto Bricco Asili down the drain a year or two ago... the wine was in great shape, except that it was undrinkable. I am sure that we have all shared similar unfortunate experiences from time to time.
Please don't get me wrong; Le Cadeau is still in natural cork and that is an intentional decision (obviously). I'm just noting that there's at least one synthetic closure "out there" that seems to be worthy of serious consideration. It certainly has my attention.