The real value of a junior engineer is that they will become a senior. That's really always been the case IME. Juniors in the first year or two of their career are routinely a net negative, maybe break even. But the thing is, unless you're making the bet that LLMs are going to _entirely_ replace human SWE, we as an industry have to maintain a pipeline to take in juniors and level them up. If we don't, we're going to be in real trouble in about 10 years.