A boring technology is one with which a large number of developers have previous production experience with. Or probably even "of the developers you can realistically expect to hire".
Better yet, hire developers who enjoy and excel at selecting and utilizing emerging technologies that will be a better long-term fit for the problem at hand. This is of course more difficult, but makes for a better team and product. I want my competitors to be afraid of technology and to de-prioritize hiring generalists.