It is also the only note taking system I have seen that will let you link to an email. If you want to add a todo entry deep in some meeting notes reminding you to checkup on that email in 3 weeks, you can. And those todos will then show up in your agenda view.
Unfortunately this doesn't work if you don't already use Emacs as your email client, which I guess you don't if you aren't also using org-mode.
While actually editing, org-roam has simple double-bracket syntax that auto-completes existing filenames. If filename doesn't exist, it is created when the link is accessed first time automatically.
Hierarchy gets established automatically as I track back links, or via org-roam graph view. But really, once I started linking notes extensively (because its so easy with org-roam), I realised that my structure ended up mostly as a graph rather than tree. However, org-mode itself has excellent tree style syntax within individual file, which comes in handy.
Searching/analyzing can be done either from withing Emacs via elisp or externally via ripgrep/fd (I'm still noon at elisp)/
I'm still shopping for a good vim-based note taking solution.