The security part is no free access local disk access from browsers without user input, thus requiring picker tags. On export the local safe folders are fine, but the preview runs in the browser, so it won't work.
Besides that, asynchronous file operations to local files has its advantages and disadvantages, and asynchronous is what we have to work with now.
Exaggerating something 10 lines of code doesn't help your case much - it went from one to two events. And could probably go back to one if you used the wait for previous action to complete action, but I haven't tried. If you're experienced with large projects then one additional event out of thousands should not make any noticeable impact on anything in your workflow, besides having to learn something new (which you also have an option not to, by using whatever version of C3 you are more familiar with if you want).
Otherwise if you're going to keep this belligerent approach then I'd just assume you're just rage baiting and not actually looking for help. Then good luck with your project.