Emboldened by the dotcom bubble (10 years ago), such narrowness of thinking is paraded as the wisdom of experience, and its current target is Twitter.
Recent Ragan research found that 54% of communications professionals think Twitter is a fad and only 8% of advertisers see Twitter as an effective promotional tool.
One marketing blogger said: "There's a lot of evidence that Twitter is simply working its way through the potential population of triallists. Once these are exhausted, it has nowhere to go. That's why it's a fad without a future."
A "senior client" came up with this brilliance: "You only have 140 characters to play with, so it's difficult to communicate the brand values required to support a business case." Oh dear, somebody stop his bonus.
Okay, I admit that originally I thought Twitter could only be of interest to eight-year-olds to gush that it's chicken nuggets tonight. I signed up (crimson twit) as I do for everything and, yes indeed, there are many people who use Twitter like that - "I'm having a delicious cappuccino". So after a brief scream, you ditch them. You soon learn not to follow your friends. That's Facebook.
Instead, you find authentic voices at the centre of trouble spots. CNN's excellent free news alert. Stephen Fry and Peter Serafinowicz for prolific and cheery chatter. And then you sign up experts on your passions.
Lance Armstrong has more than 1.8 million followers, a circulation bigger than many national newspapers. He now favours tweets above media interviews.
Al Gore does mainly green stuff for his 1.5 million audience. Coldplay tweet a daily fanzine to 1.7 million devotees. Martha Stewart's media empire is enhanced by her 1.3 million followers and Rosemary Conley will tweet you a daily fitness challenge.
This is the point, isn't it? Twitter is a media solution, not a creative challenge. It's not about jamming copy into 140 words.
Here, we have a daily signpost that people pick up through natural search and sign up to hear more.
This process of discovery, trial, adoption and rejection is nothing less than natural selection of the real opinion-formers in travel, music, finance, technology - every sector under the sun. And networks of interest are forming around these nuclei.
Any use to marketers?