The issue with the manufacture costs of such highly complex chips is also coming from the race and competition each node brings. This race is getting more complex and the market did not catch up.
They have to cram more and more transistors, and design new processors, but the consumer market did not catch up. We are still, most of us, on displays that have way too many FPS from these cards, so the manufactures don't have what to push to the limit anymore for these gamers, as they got plenty of FPS already. On the otherhand, RT seems it came a bit too slow to the market and the price is all of a sudden too high, even though the hardware is capable, its complexity grew tremendously all of a sudden, too.
They won't deliver 26billion transistors to the main stream, as the the main stream has no potential to grow, unless everyone affords RT capable hardware and is willing to sacrifice fps.
Its interesting that phone processors for example, passed 10 billion transistors mark, but there the demand is only high in gpu area for the mainstream consumers.
Nvidia should have entered mobile gaming somehow, then they would have had the incentive to bring billions of transistors easily to the open mainstream
https://cdn.mos.cms.futurecdn.net/9JqECJmZZeoXg9ekxYvcJf-970-80.png.webp