>>kachnu+pl
I think he means there are few operating systems out there that make security the primary goal. Most other options seem to think in terms of "how can we best secure the platform we already have and is used by millions of people
without breaking anything".
When that's what you're working with, you're limiting yourself quite a bit in terms of adding new security solutions. At best you'll be at least a decade behind the innovators in security who aren't afraid to build new stuff from scratch and break the old stuff.