"Our founding engineers had learned from their experience working at Google and Facebook that to ensure a performant and stable application, they would need to build their own framework"
Wow. Interesting.
Wow. Interesting.
There are definitely good reasons to build your own framework but performant and stable applications isn't one of them. Usually it's a solution looking for a problem.
When they built Luna stuff like react didn't exist.
Investing in developer tooling including frameworks is a fine use of time and often pays off hugely. There wasn't a better alternative 11 years ago.
Luna had some of the same concepts underpinning React, about 5 years earlier.