If a glass costs €1 and lasts 1 year, and an unbreakable glass costs €10 and lasts 5 years, that's not a big win.
The point remains, longer lasting glasses may or may not be superior.
But kWh, or grammes of glass, or carbon credits, or whatever you want.
Normal glass is very recyclable and doesn't require a lot of energy or resource to recycle. "Long life" glass may well not be recycled at all.
Now you're paying 5x more for 1.5x life. etc etc.
Seems to me like they last long enough when taken care of, and in situations where you don't the "unbreakable" glass splinters into a rather nasty dust like material.
Edit: Apparently glass cookware and drinking glasses are often not recyclable. This seems like a more important aspect to improve than durability even if, again, still overall a small improvement compared to overall glass industry.
Broken glass has to be cleaned up, causes injuries, even causes lost product in some situations.
I was in a cocktail bar once with three friends who ordered us the same chilled cocktail, served there day in, day out, and as the cocktails were poured into the glasses, three of the four glasses broke. Plink, plink, plink.
Glasses too hot, cocktail too cold, some other handling problem. Who knows. But tougher glass might not have done that.
Make all glasses recyclable. Probably more important but less marketable for a new startup idea...
Ironically, most of his patrons were medical students.