You could make maybe ten transistors or so, but no more. That technique is quite literally pushing atoms one by one with a sharp needle. Not scalable, though maybe useful for some quantum computing platforms’ fabrication since we’re at early stages.
And you could write nice sci-fi about subatomic transistors, but forget making them in this reality.
Yes, single-atom manipulation has already been demonstrated:
* https://en.wikipedia.org/wiki/IBM_(atoms)
Can you make transistors using that technique? Can you smaller?