I didn't read it as demeaning. I would respectfully like to posit that perhaps you haven't fully thought through what makes EN and its ilk different.
Yes a full text search and wiki linking interface would get a fairly large chunk of the essential functionality done. But there are MASSIVE gaps there. For one, a wiki is a web interface. Those are slow and suck on mobile. I've yet to see one that doesn't. Attaching media is painful. Theres no web clipper support. You'll have to roll your own infrastructure including backups. Capturing anything outside of a traditional desktop context is going to suuuuuck. Capturing TEXT is a fairly trivial problem. So much of what I capture in a given day is much more than that. I regularly scan documents and use EN to manage a paperless office for instance. You can do that with a wiki I suppose but it's more friction than is worthwhile IMO.
If you practice GTD like me, you need a trusted repository for capturing your thoughts, items, todos, etc. It should be fast and easy and available everywhere. Thats The value prop that EN brings to the table. No matter what it is you want to capture and store, no matter what platform, they have a way to quickly and easily do it. You can even email notes right into it (they give you a special email address) which I use for things like tech newsletters and stuff. So while you are right that notes apps have been around, its the little things that really make the difference here.