I've liked some Guy Kawasaki articles, like the 10/20/30 rule of PowerPoint, but this article seems hastily written.
Another fallacy is to think partnerships are bad. Partnerships are great in certain markets. Seek out people... you'd be surprised who'll take a phone call.
The problem is that other people will hate working with you and your family. You will fail to recruit the best, you will have to pay the workers you do recruit more money, and morale will always be lower than it would have been if you had not hired your family. Other employees will simply assume your family gets special treatment. (And they're always right.)
Of course, there is also a difference between hiring family and cofounding with family. If you cofound with a spouse, this problem might be unique to a startup environment where your early employees expect to be treated as equals. In a more traditional business, it's definitely not an issue.
Kawasaki's comment ignores the upsides of working with your spouse. You can both keep longer hours. It's easier to balance childcare needs. You can get another unquestionably committed team member.
Singling out family involvement is a fallacy. There are thousands of successful family businesses. There are hundreds of thousands of companies that fail that never even considered hiring a spouse. There's simply no data to back this point up, just supposition.
This is different from saying "well, Uncle Murray needs a job so I'll hire him to do my bookkeeping"--that's much more likely to be A Bad Idea.