I do not think it’s that straightforward actually. WebViews are JIT compiled which leads to big performance gains. React Native only can use a JIT with Hermes and Hermes is just plain worse than something like V8 with JIT enabled.
I don’t think RN can use a JIT at all on iOS. Only WKWebView processes can due to Apple’s security model. This makes Capacitor JS significantly faster for certain workloads
You should try to communicate more forthcomingly that CapacitorJS bundles the webapp with the native binaries, which means that you get better startup performance, but at the cost of not being able to serve the webapp fresh from the web (instead having to go through app store review process on every update like with native apps).