That claim looks to be coming from the opposite of Occam's Razor. Them doing typical SV dirty plays is a lot more easier explanation than the straws you are grasping at.
Codegen was still done via LLVM. LLVM supports the MSVC _runtime_, here they're talking about using their (arguably worse) backend directly to generate code and do optimisations
Mercor, Tacit Labs, Handshake AI...
I suspect companies like these play a big part in model improvements, generating high quality benchmark/task-focused data for training.
However, these do require educated, white collar, workers.
Considering that frontier scientists and engineers in the US are currently taking home seven (or even eight, in some cases) figure salaries - pretty high, I'd reckon.
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