Is this article telling the story of someone who's been on the JEE for 12 years, loves it, and would certainly choose it again. While I'm happy for him, I dont think it makes a good case JEE as a "startup's secret weapon" (SSW). By hypothetical comparison, if someone used 6 major tool chains for the last $DOUBLE_DIGIT_NUMBER years, and by comparison says one particular tool chain is an SSW, then I'm much more incline…
That said, it DOES mean that they have been happy with Java EE and have been so happy that they choose it again for their latest startup.
Contrast this with a typical startup where engineers always seem to hate whatever they used before and are like children in a candy shop for having the opportunity to use whatever we think is cool here.