You'd hope they benchmarked the old native iOS app and the RN app.
Since the blog post doesn't mention previous native-only perf, I'd assume they didn't compare or the RN version isn't close to native-only perf (leaning heavily towards the second reason).
Looking at a previous blog post, the first hunch seems to be correct - the second may also be true.
I hope they benchmark their load-screen time with every release/CD to stay on top of any regressions, otherwise, there'll be more mad scrambles when the perf debt piles up too high.
Since the blog post doesn't mention previous native-only perf, I'd assume they didn't compare or the RN version isn't close to native-only perf (leaning heavily towards the second reason).
Looking at a previous blog post, the first hunch seems to be correct - the second may also be true.
From 2024 March, https://shopify.engineering/improving-shopify-app-s-performa... talks about how their RN-ified app was loading screens in 1400ms (P75) and the steps they took to reduce that to 500ms.
I hope they benchmark their load-screen time with every release/CD to stay on top of any regressions, otherwise, there'll be more mad scrambles when the perf debt piles up too high.