I think part of the problem is that we are "testing" or "challenging" someone. This implies a level of distrust and hostility which only serves to heighten stress levels in what is already a very stressful situation.
You're 100% on-point. Regardless of medium (whiteboard, live-coding in a shared editor, timed coding challenges e.g., Hackerrank, etc.), these are still less-than-ideal ways of evaluating someone. Enough that there's a cottage industry of tech interview prep companies out there which I feel are exacerbating the problem.
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