Often it's infeasible to justify rewriting a lot of existing code, but my point is that these days this concern shouldn't really be an obstacle to integrating a new codec.
It should certainly lower the bar of adopting a new codec if the implementation is in a memory-safe language.
Even so, it is more code, and somewhat more risk. Lack of safety elsewhere might end up using code that is otherwise safe in order to build an exploit (by sending it something invalid that breaks an invariant, or building gadgets out of it, etc.).
