Why would that be the case?
If you think about how searchers search for information online, they almost always conduct searches based on keywords - not brands.
For instance, a searcher in Adams County, Pa. looking to buy a house will likely search for "real estate for sale" and then they might add a specific geographic area to narrow their search. But they are more likely to conduct a generic search for real estate for sale than to search for a specific real estate agent or broker. The same goes for searchers looking for information on purchasing an automobile, researching iPods, and those looking for suitable golf courses.
Generic domain names match the needs of searchers seeking information on generic topics. If a searcher is looking for a specific brand, they are more likely to type the name of the brand into their Web browsers. Or they might search for that brand.
Bottom line, if you want to cast a wide net and snag prospects looking for generic information, then target them with a generic domain name.