If AI is really wrecking the job market structurally due to new efficiencies, one would hope those effects will be permanent (i.e we won't need juniors anymore because AI will fill those spaces permanently, with or without human intervention; and thats not going to change because AI is only going to get better, blabla, yada, yada).

If it is not, it would be a matter of eventually reaching AI winter status and/or just finding a new thing to hype and the tech job market will open its gates again.

Of course there is some nuance to it, both things can happen at the same time with different intensities.