That would change the default behaviour of tap-and-hold, which is (at least on Android keyboards) to select the current word. In my experience, sites which change otherwise global default behaviours are annoying to use. i recently integrated a fancy JSON editor into one of my web apps and it changes tap-and-hold behaviour in a way its developers presumably think is helpful but which only annoys me to no end by effectively disabling the standard select-current-word feature.