The typewriter changed the way writers worked. It is largely responsible for the mindset that says write a first draft without editing and then go back and rewrite. That was what worked with typing, where editing as one goes is difficult, if not impossible.
In an earlier time, authors wrote with a pen. This made changing the work as one went quite a bit simpler. One could cross out, mark up the margins, insert passages, without too much difficulty (though it might look rather messy!). It could also be noted that the editor in the 'modern' sense barely existed then. Writers (most of them) certainly asked the opinions of others on their works in progress and made changes accordingly. But the idea of an editor as some sort of co-writer did not exist.
I never took to the typewriter and did the bulk of my own writing, once upon a time, with a pen, only typing up the late drafts. Some of my poetry still starts out this way. But the computer changed everything.
There is no longer a need for separate drafts. We can edit and change readily as we go along in word processing programs. For me, and many other writers, this is better; there are, of course, those who prefer the other approach and that is a personal choice. What matters is that it works for the individual. Isaac Asimov credited the typewriter for his voice, saying it would have been much heavier had he not been able to sit down and quickly turn out stories, as quickly as the words came to mind, without editing. But that is definitely not me, a guy who labors over the right word. That, perhaps, is due to being first a poet and songwriter.
Since I do work with at least a rudimentary outline and deal with any plot problems there, the writing itself is sometimes a paint by numbers exercise, filling in the drawing with the proper colors. In an earlier age, I might have been the sort to use file cards or such but that is no longer necessary; instead, I have two instances of my word processor (usually Open Office Writer) open on my wide screen, one with notes and outline, one with the narrative text. The fans of the unedited first draft approach might say to get ones words down while one is inspired. But for me, inspiration comes long before I actually write. I have my blueprint and my stacked lumber before I begin building my house.
The internet has also changed things. It is far simpler to get feedback on ones work now. That most of it is not very useful is to be expected but, still, being read and having the opportunity to read others is generally a good thing. The ability to self-publish has also removed the tyranny of the editor. Yes, some writers truly need ruthless editing, some are better off left alone or given suggestions.
One thing is for sure, if the typewriter still reigned I would be writing my novels with a pen. That is how I did my first one, THE MIDDLE OF NOWHERE. It is how I wrote all the articles I had published in the Eighties and Nineties, as well as all the poetry I turned out up until fairly recently. But the transition to computer was quite painless and my workflow did not really change much — it just became a little easier to organize it!