"What's wrong with being a boring kind of guy?"

In this quote, George H. W. Bush is recommending that there is nothing naturally unfavorable about being a "boring" kind of person. He is most likely responding to criticisms or understandings that he is not interesting or charismatic enough as a public figure. Bush is saying that it is more important to stick to one's principles and be a constant, reliable leader than to constantly be attempting to amuse or impress others. He is stressing the value of stability and consistency, rather than constantly chasing after novelty or excitement. Ultimately, Bush is protecting his own personality and management design, while also making a wider statement about the importance of reliability and predictability in society.