If you do everything the way the average startup does it, you should expect average performance. The problem here is, average performance means that you'll go out of business. The survival rate for startups is way less than fifty percent. So if you're running a startup, you had better be doing something odd. If not, you're in trouble.
That said, quoting for example jdiscar (https://news.ycombinator.com/item?id=11804709), "'Choose the tech I know best'" is a better metric than "boring" per se. Circling back to Graham, perhaps you should defer doing a startup until you know enough "non-average" tech.
And I add this rule of thumb: adopt at most 1 new (big) technical thing. With everything else you'll be doing, you're not likely to be able to come up to speed on anything more.
And very possibly that one new thing is built into what you're doing, such as applying technology you know at a qualitatively greater scale than you're familiar with. I saw this a lot in the late '80s and '90s when PC architects familiar with single user systems tried to make the jump to multi-user client server systems.