Never ever too old, Charlie.
Many times "new" BMW designs would be evolved from previous parts. On the /2 engine the camshaft is gear-driven and also has a magneto hanging off the front end. The centrifugal advance (etc) is attached via a taper and IIRC there is a multi-step tapdance to getting the ignition set up which involves loosening and aligning things.
The pressed-in drive quill makes sense in the context of being a /2 carryover, and makes some sense in that the later "Beancan" designs didn't even use that quill.
We'll see if there is a way to salvage this. Even if the camshaft needs to be replaced, I'm thinking it can be done without engine removal and complete teardown.
Here are links to a couple of /2 cam/magneto Fiche pages from MAX BMW, FYI: