That won't be a hard limit. Your link says that it is a perturbative theory; it ...

AnimalMuppet 5 months ago | parent | context | favorite | on: Physicists may now have a way to make element 120

That won't be a hard limit. Your link says that it is a perturbative theory; it won't hold for a velocity that is a significant fraction of the speed of light. The Z/137 formula won't hold for large Z.