Jonathan Miller is one of those multi-talented people whose stars shone brightly for a time but then faded, leaving a sense, perhaps, of promise unfulfilled. I know that Miller has expressed some regrets about the course his life has taken. He sees himself, I think, primarily as an intellectual and a man of science rather than identifying fully with the areas in which he has spent the most time working and for which he is mainly known (entertainment and the arts).
I agree with most of the points that Miller makes. Assimilating Jews are all too often seen by other Jews as betraying their heritage. I understand the reasons for this but, like Miller, I think it's nonsense to talk about betrayal.
I don't know the details, but all of my most recent Jewish ancestors took an assimilatory path. On what grounds could we deem their decisions to be wrong or unfortunate? They made their choices on this and many other (often more important) matters: it just seems inappropriate for others to pass judgment.
If one believes in the basic tenets of Judaism (however they might be understood), then – sure – it may seem unfortunate that someone born into this faith decides to renounce it. I know that Judaism is not a creedal religion like Christianity is, but (as I see it) it only really makes sense as a religion if it is seen to incorporate certain beliefs (for example – and most importantly – that the God of the Bible is real in more than a mythical, symbolic or psychological sense). Miller also sees the issue in these terms apparently. He says he can't accept "the creed".
If you set aside Judaism there are still of course many valuable things which could be seen to characterize modern Jewish culture (or, more accurately, cultures). Intellectualism, respect for learning and education, a certain kind humour... One could easily extend the list. But I don't see how one could find in such things a compelling, unifying force, something strong and coherent enough to hold all those with Jewish ancestors together as a people going forward.
A shared history of oppression? Yes, Jews have often suffered discrimination and oppression, but these experiences varied from place to place and from time to time. And not all Jews suffered in this way. It is not a defining feature of being Jewish (as being associated with Judaism is).
It would be interesting to know if Miller's views changed as he got older. I may follow up on this.