“If PEP 703 is accepted, Meta can commit to support in the form of three engineer-years (from engineers experienced working in CPython internals) between the acceptance of PEP 703 and the end of 2025, to collaborate with the core dev team on landing the PEP 703 implementation smoothly in CPython and on ongoing improvements to the compatibility and performance of nogil CPython.”
Guido asked for engineers with CPython internals experience. Meta offered three engineer-years through 2025, and only if the steering council says yes first. That is roughly one and a half people for a change that splits Python into two builds and makes every C extension author ship both. Meta gets its threads. The volunteers get the support burden for years.