If anything, a PhD program teaches you how to write faster while maintaining an acceptable quality: Journal papers, conference presentations, and funding agency

If anything, a PhD program teaches you how to write faster while maintaining an acceptable quality: Journal papers, conference presentations, and funding agency reports are all long-form writing projects that come up quite frequently and distract from the research (the fun part). Most of the value from this writing comes from it being accepted; improving quality beyond this level has rapidly diminshing returns.