[flowerthoughts]

1. This is already the situation if you don't have technical knowledge in-house and outsource all development.

2. Yes, if you only have few people who know how to use a powerful tool, they might have leverage.

3. The supply-demand mechanism is certainly there, but the time scale is never mentioned. It'll take time to remove the unemployed juniors from the pool (maybe they get sucked up into other jobs.) It'll take time for seniors to realize they have leverage. And, of course, the company must not have rehired junior engineers for other reasons (e.g. because the coding tools become so good that seniors are not needed.)

Any objections about "this thesis isn't true; look around you" needs to take this into account. The argument is not that we're there now, but that there's a mechanism to lead there.