> I think that the radius of a Silicon atom is about 0.1 nm. ~1 nm may be the limit of what's possible. The next nodes after 3 nm are likely going to be 2 nm and 1.4 nm.

the node names do not represent any actual measurement of the chip anymore, and have not for at least a decade. There is no measurement of a "5nm" chip that measures 5nm, and scaling is in fact largely dominated by how close you can place the transistors, not the actual transistors themselves.