And I thought Intel's 14 was good too (after some ramping), which is why they stayed on it and iterated on it for so long, it was the 10nm process they had so much trouble with and the problems there are not generally reported to be with lithography but materials (cobalt, among other things, which they dropped in later nodes).
So I'm not sure what you are trying to argue. DUV has _proven_ to be economical down to about 7nm.
TSMC's DUV 7 processes are reportedly very good.
And I thought Intel's 14 was good too (after some ramping), which is why they stayed on it and iterated on it for so long, it was the 10nm process they had so much trouble with and the problems there are not generally reported to be with lithography but materials (cobalt, among other things, which they dropped in later nodes).
So I'm not sure what you are trying to argue. DUV has _proven_ to be economical down to about 7nm.