10nm was the first node to use the problematic features, but Intel certainly hoped to use the same technologies at smaller nodes as well. Cobalt and COAG become

10nm was the first node to use the problematic features, but Intel certainly hoped to use the same technologies at smaller nodes as well. Cobalt and COAG become more relevant, not less, with finer features. As for whether or not they will eventually work, that's the many-billion dollar question. In mid-2018 the boots-on-the-ground were not hopeful (the "10nm will never work" leaks) but clearly someone at Intel thought there was hope because they didn't just abandon the features. I think we just saw that "someone" get fired, though, so I suspect the attempts to save these features have failed.