I feel like they fill separate niches. I really enjoy Obsidian for notetaking, but the Zotero collector for web browsers that saves and organizes all your references is a godsend. Granted, this feature might be in Obsidian but I'm not too familiar with the plugin landscape for it.

if you like obsidian and zotero, try logseq!

I second this. I use it with Working Copy app to sync notes to a git repo.