Why is this? I'm drawn to WP for my own personal site, because there is a critical mass behind WP, it's a transferable skill, there's a lot of nice stuff that comes out of the box, there's a well established web design community around it, etc.

I've seen so many static site generators come and go over the past decade that the number of options now is just dizzying. From what I've seen, they all try to be "minimalist"... until the developer realizes there's a lot more work and expertise involved in "minimalist" design than they originally thought, and they grow, bit by bit by bit, etc, ... Then somebody sees these "bloated" SSG's and decides to reinvent the wheel by creating their own "minimalist" SSG with no baggage and thus the cycle starts all over again.