On Ghost Explore directory homepage and all categories, Google will only ever see the first set of results.
Googlebot doesn’t scroll - so the existing infinite scroll implementation means that they never see any blog beyond the first set of results to load (18 blogs).
To fix this you guys could implement normal/search engine friendly pagination, ie using actual clickable page links - or at least have a “Load more” button.
You can verify this by typing
cache:https://ghost.org/explore/ into Google or Chrome.
I realise the directory isn’t necessarily designed to be used by search engines in the first place, but it seems like a wasted opportunity for everyone.