We are focusing on higher priority tasks and will not be addressing this any time in the near future. Perhaps it may seem like a simple addition, implementing it correctly could/would introduce unforeseen complexity. And, well, since call recording is already available in the Dialer app, expanding on this feature kinda isn’t a justifiable use of time and resources when higher priority features remain in development. I mean, we would maybe consider an external contribution, provided it meets our standards for code quality, maintainability, and overall design.
Also there's many similar threads on this topic here already and an older official statement:
https://discuss.grapheneos.org/d/5413-call-recorder-automatic-recording-of-calls/40
On another note, curious as to who you mean by "We'll fund it"? Are you representing another business or project or organization of some sorts? Or did you mean in general?