Help! My developer won't implement / wants to remove / objects to my redirects.

A client recently asked me to chip in on a debate they were having with an internal tech team about retir­ing old 301 redir­ects. Concerns had been raised about ageing and legacy CMS func­tion­al­ity which needed to be replaced, and as part of this process the IT folks pushed to remove (and not replace) the thou­sands of redir­ects which the system was power­ing.[…]