I think it just depends on how you're able to access and use your notes. For me, backlinks were a life-saver because it's important to model relationships between individual notes. It's really helpful for synthesizing knowledge and creating output, or just exploration to find related ideas, etc. Backlinks also help with breadcrumbs, so if my memory fails (frequently) or my search fails (more often than I'd like), I can usually find what I was looking for by navigating backlinks or using hierarchical breadcrumbs (all generated automatically with backlinks in a defined property). So I get a bunch of bottom-up organization for free with minimal effort, and for me it's pretty helpful. Plain textfiles I have trouble resurfacing knowledge very quickly, but YMMV, it's really personal.

The nice thing about obsidian is that you can start off really simple. It can be as minimal as linked markdowns documents if you like. Which is pretty much most of the core plugins disabled up to all the bells whistles.

I've never used org-mode so can't really comment on whether you'll actually be gaining anything