How biased are you when you compare/review keyboards and what brand do you place on a pedestal without merit?
Fairly easy
The more the publicity, the less likely the device is worth as advertised. Advertising is the fundamental bet that your product is so ****ty you will not be able to meet minimum profit revenu, therefore you spend more to attract people into buying your item, aka create "the need" or "the want". Also, it floods the market, and "the cult" can't all be wrong, right? Also, companies that are in multiple fields are usually bad at multiple fields. I'd rather get a keyboard from a company that makes keyboards only now-a-day.
Therefore Razer, Corsair, Roccat, CoolerMaster or any other big e-sports sponsors are always at my bottom. I will still judge impartially when it comes to test these devices, but usually i already know what i'm in for.
Look at Razer; some e-sports player "speaking words of wisdom" on their product page, e-mails for 1337 PACKAGE IF YOU ORDER ABOVE 200$ IN LESS THAN 20 MINUTES, Runes in league of legends... flashy random colors on your devices... Razer is the number one device maker that want to flood the market and over publicise as much as possible, they give you stickers with every purchase, stick them to your stuff, it's a "cool" brand.
Companies that i've never heard of usually tend to shine a little more later on because their products are worth the shot. Best example is KBC, i've had this Poker II for a year and 3 months now, i simply love it, always worked flawlessly and guess what, i am not alone sharing this opinion. For the fourth time, the Poker II appears on Massdrop. That's a company that never ever did anything to advertise it's product as far as i know, yet got reknown simply because it's products are a fair trade.
But still, i am biased cause there are some that i appreciate in them. I like Steelseries a lot just because their devices are "classic" (read, swag), and i've been using them since a lot of time. They are pretty silent tough, no junk e-mails or random ads. Even at e-sports events.
I am totally biased by my many years of experience with multiple computers systems, debugging, repairing, and gaming. But bad sh1ts make good stories, right?