war on drugs was their reasoning; not sure if it's true or acceptable and yeah I'm pretty amazed it flew in the US.
But then another brand by Corning is the same, they had a range of unbreakable product called Corelle, the new stuff since it got sold off just isn't the same.
Old school Corelle is the best ceramics you could get. I have 40+ year old Corelle plates and bowls in the cabinets right now. Used daily and dropped hundreds of times over the years.
I'm not sure how their PR dept spun it but borosilicate glass is incredibly resistant to sudden changes in temperature as well as having better chemical and acid resistance making it ideal for chemistry lab work, presumably some news stories broke about 'amateur chemists' using Pyrex cookware for a different type of cooking. It's not like borosilicate is a controlled material though, the reason for the switch is likely that soda lime glass is significantly cheaper to produce, they did suggest that their soda lime glass was more mechanically durable but then again borosilicate glass is also known for being mechanically durable.
But then another brand by Corning is the same, they had a range of unbreakable product called Corelle, the new stuff since it got sold off just isn't the same.