Well, for starters, you can't judge an entire era of Lionel production based on a single engine decades old that you bought from another owner. You have no idea what the real history of that engine is, although to you it appears new. Even if it were new, there is no logic in concluding that an imperfection in one engine warrants a generalization about thousands of engines made during a production period that lasted for years.
It's possible that you just got an engine with a very rare defect, or, more likely, that engine you got has a suspicious history, especially considering that not one but the armatures of both motors are allegedly bent.
Personally, I had a set of LTI Santa Fe Warbonnet engines years ago, no. 11711 from 1991, and it ran very well and for a long time.
