When one says truly native, that is an even stronger claim that, in my opinion, directly communicates we are talking about byte code. On iOS, for example, native means Obj-C and Swift. When I read someone has created a framework/library that provides truly native apps using X and Y, my immediate expectation is we are talking about X and Y compiling down to platform-native byte code, with no VM, unless the platform itself is a VM. An example here is Elixir compiling down to truly native BEAM apps.
For the web, JS is truly native. There are a host of other non-JS technologies that compile down to truly native code for the web. I’ve yet to see any JS technologies that compile to truly native platform code for desktop and mobile (except mobile platforms which use web technologies as platform-native code)[0].
[0]: A quick perusal of NativeScript claims it does not use web views. If it actually lets you directly create and use a UITableView, UIButton, UIListView, and the rest, then perhaps it can qualify as native UI. But there’s still a bridge to cross from there to truly native app, and I’m unsure if it actually becomes 100% platform-native code without a JS VM involved the way, for iOS, Obj-C and Swift are.