I frequently have to remind my mother (in her 70s, and tends to believe everything on the internet) not to rush through a Booking.com transaction because "rooms are selling out fast." Or not to favor Booking.com because she was given some "insider discount" (forgot the exact phrase) for repeat business.
As the article states, plenty of rooms are still available for a given hotel no matter what Booking.com claims. And that "insider discount"? I got the same price as her while logged in on a brand new account.