In the transcript I found more talk about porting C++ and Go to Rust, without Python rewrite references... still interesting tidbits, like
"when we've rewritten systems from go
into rust we've found that it takes
about the same size team about the same
amount of time to build it that is
there's no loss in productivity when
moving from go to rust "
I don't think it was on-device code, as they talked about porting Python projects. But you can watch the talk to see if I'm misremembering.