@lanodan @mia For me it is mainly the form factor: laptops being both too small and too bulky for writing. If somebody put a large-enough Cintiq on my desk, I think I would take my ad-hoc notes on that no problem. (However, it would have a different feel to it…)
The only platform that comes close to being a portable alternative for paper is probably a reMarkable, which is still rather small and expensive. (I don’t know what the state of PineNote is now.)