There is things you really can't do by yourself. I've been working on porting some large codebases to Rust lately to experiment with fixing memory safety bugs. There is just no way you can write 100k LOC in a week of production code with tons of tests etc. Even "10X" engineers just can't type that fast.
What language you are trying to port from?
How would one even know if the port of 100k LOC was successful? Are there language-agnostic tests (CLI STDIN/STDOUT) or similar involved?
even if that were true its the exact opposite point the article is trying to make