This is another ridiculous straw man. It is perfectly evident that hotels associated with hotel management companies or brands can be every bit as diverse as independent hotels. What chains bring you is a level of service guarantee, booking and often some form of frequent traveler benefits. What independent hotels can offer in some markets is greater choice and diversity in the service experience (for better or worse).
Anyone who would avoid a hotel simply because it's associated with a brand is making a political or "ethical" statement, rather than making an intelligent decision based on travel preferences. But, as ever, to each their own.