For a product that is responsible for billions in revenue every year, I would expect them to have some of the best native developers working on it. Instead, they sorta wrangled web technology to sorta work. I don't understand why the performance is so bad on the PS4 of all things, given how it's a pretty decently specced machine.
They, and many other companies, should really look at the iPhone's early success - a BIG factor there was native code, meaning they could run on a single core machine for years while Android was struggling to push device specs up just to get their UI to feel performant.
And Apple's wasn't even optimal; they used objective-c which adds some overhead with every single function call (simplified: 'can I call this method on this object? Yes? Then call the method on the function call'. Only fixed with Whole Module Optimization in Swift iirc).
But it made such a huge advantage in terms of performance and battery life, Apple was easily five years ahead of any competition.