Most things are web applications and you can edit those - sometimes people even do it with browser extensions.
The reason you can't do it the rest of the time is because developers would have to support it if they allowed it, and then they'd never be able to change anything ever again. Apps also aren't set up to allow this because of Conway's law, or maybe I have it backwards there.
The reason you can't do it the rest of the time is because developers would have to support it if they allowed it, and then they'd never be able to change anything ever again. Apps also aren't set up to allow this because of Conway's law, or maybe I have it backwards there.