I guess it could help to talk to someone familiar with it, maybe they would know the lay of the land. Otherwise it’s a matter of deciphering the architecture of the ancients. Your ability to do that entirely depends on how obscure it all is to you. Many software projects have been born out of the incomprehensibility and unmaintainability of older otherwise-perfectly-functional codebases ☺️
it just depends on the specifics. a manager (or management team) can theoretically offload administrative stuff in big organizations that would overwhelm everyone at the edge to distribute