If an outsider is ever allowed to have a simplified mental model of why nvidia was unbeatable, here's mine:

- they were way ahead, and they didn't make any big mistakes

- they weren't waiting for others to catch up. They were aggressively improving

- memory bandwidth is almost always the bottleneck. Hence systolic array is "overrated". Furthermore, interconnect is the new bottleneck now

- cuda offers the most flexibility in the world of ever changing model requirements