The engineering department is overworked, and has been for literal decades. There are so many issues facing the company at any one given time that only the absolute most critical problems can be tackled, leaving everything else to grow until they become critical. There's no time to pre-emptively head off things that might become a problem or upgrade outdated, overly-convoluted, time-consuming processes.
Senior management is only exacerbating the issue by placing tight schedules and aggressive deadlines that don't factor in the amount of time engineering has to spend keeping the rest of the company afloat.