Which is odd. Windows was able to browse ZIPs like normal folders since... 98? XP? Can't remember now.

IMHO KDE delegates too much core functionality to apps. On macOS, I can press "space" while having a file selected and I get an instant preview. This sort of thing must not be delegated.

Is this true? I was under the impression windows wasn't able to decompress zip files natively till very recently, like windows 11. I could be remembering wrong.

Yeah it's been supported since at least Windows 7. I think XP sounds about right.

Windows millenium was first to bundle.

The recent update to 11 added libarchive integration with bunch of formats

At the very least it does add context menu entries for compression to files, apart from "open with" obviously. That might already the reason right there.

So I can't install an app that adds context menu entries? I can do that on Windows.

Yeah obviously. Windows let's everybody and their dog write into the registry.

Which goes completely against the kind of immutable and sandboxed system that KDE Linux intends to be.

That likely depends on the desktop environment. I have packages installed on my steam deck that add context menu entries, so clearly it's not impossible (my system still remains read-only, though I've been thinking about using an overlay like rwfus to get some new native packages, due to annoyance of self-management of self-built and downloaded ~/.local stuff)