Earlier quoted context omitted.
If you think professional sports leagues and the movie business base opportunities and compensation on seniority I don't know what to tell you. Those fields are almost completely unionized. There's no obvious reason to think that the market for high skilled technical workers would be substantially different.
If you don't think the UAW or ILWU bases opportunities and compensation on seniority I don't know what to tell you
The difference is between commodity labor and creative, talent-driven, or IP based production, and it seems clear which is a better metaphor for software engineers.