I’d say these two probe very different things in the same way that epidemiological studies and carefully controlled studies on a small number of subjects can tell you different things. E. g. controlled studies tend to be shorter and tend to be statistically insignificant. A study with N = 10 participants has next-to-no statistical significance, for example. And in smaller groups, you can easily reach results that may or may not be directly applicable to others. E. g. do results of studies on college athletes apply to master athletes?
The other weakness is that scientists usually like to narrow their focus to dig deep. That’s not necessarily a good approach if you are closer to the application side.
That’s why e. g. nutrition is such a minefield in terms of science. I am a scientist, that’s what I get paid to do. But I found nothing harder than finding scientifically grounded information on nutrition. And this debate has a flavor of many keto aficionados vs. vegans debates.
And we shouldn’t. However, I’m assuming you — just like I am — are not an expert in the field of sports science. After hearing everyone out, isn’t the decision that you find one side more persuasive than the other without sufficient domain knowledge as a decision you take on faith or instinct?
My impression of the deep dives by Coach Chad and Amber (should I say Coach Amber) have a deep background in the subject, both, from the scientific end as well as the practical end. They “speak my language”
(in a very different dialect), so it seems they are used to working with the scientific method.
I also have a good impression of Dylan, I sometimes watch his videos, he is clearly a talented athlete who has a very good scientific background.
Like I wrote earlier, I really look forward to TR’s opinion on the subject, e. g. whether Amber has done polarized training as a pro or whether she knows teams who do follow that approach? I’d still have to take some things on faith, but understanding their reasoning better would give me a deeper understanding of the subject.
And I think this skepticism is good. At least business-wise, I see no misalignment, though: TR’s interests seem perfectly aligned with picking the best training methodology available. It’s not like search results in Amazon, which have become useless.
From a competitive standpoint it is their trump card. 
PS Just to double check: do I have that right that you think polarized training is better? If so, why do you think so?