I am not knowledgeable enough in these matters to debate this
I would like to think I am, you can take my word for it or not as you will.
My initial impression is that Warren knows enough to get herself into trouble. Unlike some liberals, she is aware that Glass-Steagall worked quite well back in the 30's, a time when banks were the only institutions that granted credit.
However, that is no longer true today. She is making an inference between what worked 80 years ago and today, and that is dangerous territory.
I'll give her credit for being an interested amateur, which is more than I can say for the average poster here. But she is still an amateur.