I don't see how you can confidently say this when AI researchers and engineers are remunerated very well across the board and people are moving across companies all the time, if the plan is as you described it, it is clearly not working.
Zuckerberg seems confident they'll have an AI-equivalent of a mid-level engineer later this year, can you imagine how much money Meta can save by replacing a fraction of its (well-paid) engineers with fixed Capex + electric bill?
Does it mean they are mediocre? it's not like OpenAI or Anthropic pay their engineers peanuts. Competition is fierce to attract top talents.
Rather with AI, capitalism seems working at its best with competitors to OpenAI building solutions which take market share and improve products. Zuck can try monopoly plays all day, but I don't think this will work this time.