Read carefully: I said only rewrite if the code structure is bad. If the code structure is good, then re-architecting can amount to restructuring only the top-level parts.

It can give OP a better feel for how the code is designed, and give them more opportunity to change things in a more structured way in the long term by repeating the process (rather than just fighting fires every time).

Code structure provides very little business value.

Ten year old battle tested spaghetti is more valuable than any benefits a complete re-write would provide.