Though mechanical, typewriters are also analog and as such have character. From the hammers to the action of the keys there is something unique about each typewriter and there is an appeal. Some typewriters have very smooth action on the keys, some are like typing with a mallet. A letter is askew, the ribbon is running out. It all marks a unique moment in time. A Word file has a date stamp. Maybe built in history but no handwritten note or edit. No XXXX through a word. No inherent mistakes.
A computer doesn't age well. I am not sure how many of these machines will be working in 50 years. There is also something definite about a typewriter. You sit down to it and there you are; no playing solitaire for hours while procrastinating. You write. You can XXXX something out or throw it away, but it can't be undone.
I can see how a keyboard might be a collectible in future years but whether it is a model M or a Das Keyboard it probably wont have the inherent appeal either aesthetic or historical that a typewriter will have.