This is not a web vs. native problem. You can implement keyboard shortcuts in a webapp. You can neglect to implement keyboard shortcuts in a native app.
This is all about attention to detail, which internal corporate apps almost always lack.
You can add keyboard shortcuts to a webapp. What you can't do is control or override the keyboard shortcuts that the browser adds, and you can't make use of the full suite of possible keyboard shortcuts. I've looked at adding shortcuts to my webapps many times over the years, and it's never been worth the effort because the result is just confusing to the user.
This is all about attention to detail, which internal corporate apps almost always lack.