The Rothschild Family Still Wants to Find

Times have changed. The goal of a marketing campaign used to be to make a brand famous. And many years ago, when there were only a handful of brands and little advertising, that strategy proved very effective. For each product category, consumers tend to prefer "well-known" brands over less-known brands.
Campbell Soap. Morton Salt. Listerine mouthwash.
However, today, with countless advertisements, each product category has many famous brands. Let's take toothpaste as an example. Colgate, Crest, Aquafresh, Arn & Hammer, Mentaden, Sensodyne, Rembrandt, Close Up, Ultra Brite and Pepsodent. Each brand is quite well known.
Which brand do consumers choose to buy?