saying measurements is a source of bias is like saying knowing a dish's ingredients can bias a person's opinion of the taste.
I essentially thought the same thing. If I apply this same logic to medicine, his argument would be that I should not tell a patient how a medication works or its potential side effects in order to avoid them having an adverse psychosomatic or nocebo reaction to its administration. Who is to say whether or not said reaction was natural or induced if the result is to be treated the same? He simultaneously has his own assumptive biases while proselytizing in criticism of another.
The scientific method itself has an inherent mandatory bias to function and be a useful tool- the act of formulating a hypothesis implies one has either observed something under a set of biased conditions or that they suppose something may be true or likely based on the bias of previous scientific study or understanding. The goal is to eliminate as much bias as reasonably possible to make consistent and repeatable conclusions, and I can argue that an extreme focus on objective measures and conventions is one way to do this and will almost always be the lesser of all evils if the goal is to eliminate biases.
Most people that even care about these measurements in the first place will probably not even bother wasting their time trying, let alone buying a product unless there's at least some kind of measurement available, so to whom is his advice useful? His opinions seem aimed at reviewers, yet those that actually know what to do with these measurements don't really need an input of a reviewer's subjective opinion to make decisions anyway. So, this seems like a personal gripe of his more than actual advice for the average hobbyist.
Notice how none of these reviewers releasing these "measurement talk" videos can demonstrably prove they know anything about taking or interpreting them beyond the superficial, cite peer-reviewed publications or even books on psychoacoustics or sound reproduction, show how to manually correct a room around them etc. Shame on all of these youtubers with "fence sitter" opinions dismissively mentioning studies related to the unreliability/limitations of human hearing, while totally ignoring the wealth of information we do have, that is reproducible and proven by decades of rigour. They don't dare invoke any science that disproves their babble yet will freely cite it when it does and call foul.
The trend I'm seeing on these youtube videos is everyone coming out of the woodwork with these "apologist" videos. "Yeah yeah..measurements do matter...BUT..." and then offer absolutely nothing of value or some nonsense opinion. Their viewerbase (or new viewers) that are interested in measurements will think "hey this guy is experienced! he's opened minded and looks at both approaches to audio!", and those that only care about subjective experiences or think measurements don't matter are all but completely vindicated. They think "See, even someone that thinks measurements matter says objective reviewers are biased and my subjective opinion is the only thing that matters!".
The end result is that they appease the largest audience possible and do not particularly offend anyone. Good for viewership and to promote whatever it is they are selling.