In my experience there is only a need for Project Managers when multiple groups that span multiple functions (development, marketing, customer support, etc) are

In my experience there is only a need for Project Managers when multiple groups that span multiple functions (development, marketing, customer support, etc) are needed to deliver something and they need to work on different cadences. The Project Manager can act as a transmission of sorts to make sure deliverables happen at roughly the right times to not block each other. Outside of those circumstances I have never seen any value in it. For software only initiatives the entire project management function is little more than ignoring Jira boards and calling meetings with lots of people to “check on status”. If you have anyone doing this then your organization is in a bad place and needs to be set right, it will not get healthier.