Every field that scales eventually splits.
It always happens the same way. A new technical capability emerges. Early practitioners do everything, the thinking and the building. Then the field matures. The thinking and the building separate into two distinct roles, because the skills required are genuinely different. One role owns the investigation and judgment. The other owns the execution and craft. Neither is lesser. But they are not the same job.
Back end + Front end
Data scientist + Data engineer
DevOps + Developer
Researcher + Designer
Strategy + Operations
UX + UI ←
AX Designer + AX Engineer ←