It's def a slippery slope, but all of hiring is bound by implicit bias. If random people are evaluating random people against a set of subjective metrics, you're always going to get _some amount_ of bias in your decision making.

In reality, I think a surprising amount of bias goes into "tech screening", maybe even moreso than evaluating "soft skills." If you're asking random engineers at your company to conduct tech screens, the odds that those engineers are emotionally and mentally reflective enough to be fair and bias-free in the questions they ask and the solutions to those questions are very low. This is why so many places struggle with tech interviews that feel like debates. Engineers dislike candidates that do well on the tech portion of the screen because those engineers feel it is a competition that they must "win". I've seen this time and time again at FAANG and non-FAANG. Random engineers from a team should not be assessing candidates, pretty much ever.