Its' the exact opposite ... Google, nVidia, Amazon, Apple, etc. all have a deep bench of code that is a moat. They have lots of throwaway code too, but those companies are precisely the ones that pay attention to code quality, and comprehensibility by experts
A rough proxy for this would be if they say contribute to the C++ standards process, which Google Microsoft nVidia do, and basically zero "normal" companies (say SaaS) do. It means they are investing in multi-decade maintenance of their codebase