I've been using Obsidian for 18 months now. It's much better fit for me and I enjoy using it, rather than being frustrated all the time.
Obsidian's pace of development is impressive, bugs have been fixed quickly and the community is active and helpful. In contrast, Evernote would put me through a long bug-reporting or feature request process and then ignore it, basically forever.
It became obvious that Evernote 's development priorities were completely different to what I care about.
The big things for me are:
* I want my task management and note management together. My tasks are directly connected to my projects notes. (And I don't just mean checkbox – I mean being able to manage and filter my tasks.)
* Speed.
* Easy linking between notes.
* Excellent conflict management. (Very rarely needs intervention from me, unlike Evernote which had me mucking around with diff checkers.)
* Markdown is comfortable for me, and lets me write (and search for) exactly what I mean.
* Having complete control over my notes. I can use a different editor for a note, and if I want to do a search-and-replace across my entire vault using VS Code, I can. If I choose to move away from Obsidian, my vault is just a folder full of easily readable files (and their attachments).
* (Geeking out slightly) regular expression option for search.
YMMV, obviously.