I don't think that problem is restricted to Angular - it's one that you see with when developers wrote unmodular code period. I saw it with legacy ExtJS code.
Oh I completely agree it's not an angular thing. It was a Rails thing, is or will be a 'node' thing, etc. It will be a docker thing at some point too. There's a rush to 'new' that appears to everyone to be 'it', people use 'it' for a bit, realize it doesn't solve all problems, then move on to something else. They've done a lot of learning on someone's dime, moved on, but left a mess of code for someone else to 'maintain' for years. The cycle will continue to repeat itself for a long time...