Bad code written by software engineers is worse than bad code written by scientists, as the former takes more effort to fix than the latter (given the pathologies mentioned). It's naturally preferable to not have bad code, but it that choice was actually on the table, then I don't know who would choose the bad code.

As for hiring software devs, that's not going to change (in general, there are places where software devs write code used by scientists, but rarely are these codes themselves pushing research boundaries, it's code on top it that does) absent significant changes in funding structure and rules (which are typically a government/public service concern, and not up to researchers).