Cross platform wasn’t even mentioned or implied in your original comment by the way, it was edited into the second one where you narrowed an “arthritic, farsighted Arabic speaking user” into “arthritic”.
I’d rather pay $50 for a native macOS application that uses the UI toolkits offered by its platform and respects the conventions and the system as a whole, than to pay $5 for an application that allegedly does the same thing but which feels broken, sluggish and/or incoherent because its developers are making something cross-platform.
There are some exceptions to this – some developers do pull it off, and if what they make is both good quality and performant and the tool is offering something of exceptional value to me then I will use it. But in the general case, I will avoid the non-native experience.
All of that being said, I still think it is cool that people invest time in exploring making their own GUI frameworks. All I am saying is that it has a cost for the users a lot of the time.