RE: the last point, that doesn't seem so. Desktop apps have always been opaque, same as server backends. If anything, the rise of SPAs, WebAssembly, Service Workers and JS in general means you can see a lot more of the action in your browser rather than it being hidden away somewhere.
WebAssembly expressly has a textual representation so that it can be inspected, it's part of the spec. And for everything else that's compiled, there are always decompilers to give you the source, often times at great quality.
HTTP/2 is binary (and by default encrypted) but nobody notices because browsers and tools transparently convert it to text for you, even though there were plenty of complaints that it would be hard to inspect.
WebAssembly expressly has a textual representation so that it can be inspected, it's part of the spec. And for everything else that's compiled, there are always decompilers to give you the source, often times at great quality.
HTTP/2 is binary (and by default encrypted) but nobody notices because browsers and tools transparently convert it to text for you, even though there were plenty of complaints that it would be hard to inspect.