Scientists have produced an oxide glass with unprecedented toughness. Under high pressures and temperatures, they succeeded in paracrystallizing an aluminosilicate glass: The resulting crystal-like structures cause the glass to withstand very high stresses and are retained under ambient conditions.
I don’t think the glass makers themselves are necessarily the issue - they’ll supply whatever is in demand, including low quality crap if demand is high enough.
The existence of quality makers implies there is sufficient demand for quality
People know brand names. People don’t own glass testing equipment. People will buy cheap glass for a high price if it has a brand name they associate with quality.
Supply and demand has nothing to do with it.