I work for a small(about 50) company. The ability to write well is absolutely huge.I've seen people being refused salary increases(indirectly),not given more important tasks,and simply struggle on daily basis when they can't put in writing what they need.I wouldn't be able to count how many times I had calls from partner level supplies telling me they can't understand what the email they received from my colleague means. It's so bad sometimes I'm honestly thinking of introducing writing test for the next hires.