Windows 8, which was tablet-oriented, was one of these skip generations of windows that nobody cares about in the end, and when the next comes everybody forgets. I never installed it anyway. I have not owned a touchscreen laptop myself since then, but from friends that have and I have used theirs, it is like OP described as a "harmless additional feature/why not", something that just makes certain interactions a bit faster.
But especially on an actual laptop, one that you cannot just separate the screen from the keyboard, stuff like "virtual keyboard" and "tablet mode" matter much less because it is not like you will take it and use it as a pure tablet anyway.
We saw the same thing happen with mobile first on websites.
Or for that matter, that adding support for game controllers (something that has actually happened with Linux desktops) would led to curtailed development of non-controller parts.