The point of Zeal is downloadable docsets for offline usage (cppreference, MDN, GNOME docs, etc.), whereas Obsidian is more of a personal wiki you fill yourself AFAIU.
You could clone the doc repos and just open with Obsidian to get nice rendering.
I use cheddar for this, it’s so versatile
Do you have a link? Never heard of cheddar.
I think skrebbel was parodying prox's reply as a commentary on drive-by comments about a seemingly orthogonal technology.