"Tablet mode" was not necessary to use for touchscreen, though. As far as I remember you can have full touchscreen functionality in the default mode of windows. I had a surface pro 4 for some years and I do not remember using tablet mode ever.

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.