But THAT is exactly the fear of the acquisitions.
BRS as a sole retail entity can and did do videos for a lot of the retail products they carry because it didn't matter to them which one sold more over the other. Now that there are competing interests (EcoTech Marine, Neptune Apex, AquaIlluminations), Tunze, Sicce, Maxspect, etc compete with EcoTech products, so the jury is out currently if we will get in-depth reviews of their new products (they already haven't covered the Maxspect Jump lights or the Blue Edition soon to be coming out), my speculation is that because they compete directly with AI Prime's at a lower pricepoint, they won't get reviewed, only time will tell though.
Also, did it ever occur to you that the reason Profilux or Hydros don't have more market share is that the internets number one source of information about reef equipment hasn't showcased them? Ryan brings this up in a "History of Controllers" video published a year or two ago where a controller manufacturer was telling him "No one will distribute it if you don't talk about it, they've already told me as much". He even acknowledges in the video that that's a big weight to carry on his shoulders. The simple fact of the matter is, the Reefing Hobby Community, retailers, and distributors as well as consumers, look to BRS for product information and recommendations. If they're recommending based on only products they are affiliated/associated/partnered with, the market share of all other products goes down, leading to less competition in the market.
As for the why aren't others doing deep-dives, there are smaller youtube outlets doing deep-dives of GHL/Profilux and CoralVue/Hydros, they just don't have nearly the viewership of BRS.
