I hear that these situations exist, yet this is the complete opposite of what I was taught, which is that (at least !) the project manager had to have frequent and direct contact with the customers starting from trying to figure out what their real needs are - for the project to have any hope to succeed?
In software/tech world, PM's customer are often internal stakeholders, often not all relevant ones. Very rarely company's customer. PM juggles internal issues like milestones, priority, resources, budgets and even some politics.
I've seen proposals where one of the requirements was that the developers would have as little contact with the customer as possible. What little contact was allowed was through the most junior person at the customer.