You are mischaracterising the author who would love one. They said:
these kinds of prototypes are built to inspire and show what is possible, not to be mass produced for actual users
I spent a lot of time looking for better equipment for my mum. There's so much dangerous or unusable mobility tech out there, that is often unaffordably expensive. You usually need to buy new, because the second-hand market is abysmal, and customisation is often critical.
Rollator designs with good wheels and working brakes were what I struggled most to find. Most designs couldn't handle basic needs. Wheelchairs were a nightmare - I was just fortunate she only needed one very occasionally.