Earlier quoted context omitted.
that's like saying horsepower is irrelevant metric, lap times is you kinda need the one to get the other in the decent place, even if it is not the only one. Lack of performance WILL turn every design into mediocre or worse
Bad performance makes even good design bad but good performance doesn’t make bad design good. Looking at performance is making the second step before the first. Performance is the means to an end, but if you fixate on performance, the means becomes the end
I'm not sure I agree. Bad design can ruin a fast UI, and bad performance can ruin a good UI. I'm not sure one is more important than the other, because they're necessary parts of the UX. They should be designed for together, not independently.