While it is true the rendering engine is the same. The functionality is different. I have 5 browsers installed on iOS. They are not the same. - Brave. Has native adblocking - Orion. Supports extensions from firefox and chrome extension store (not perfect compatibility, but still quite amazing). - DuckDuckGo Browser. Offers nice privacy features. - Firefox. Allows to sync tabs with desktop. - Edge. IIRC I installed this when LLMs were early and it had built in bing chat for free llm chatting.

So while the rendering engine is the same, that is one of the least interesting things.

That said, I'm all for removing this requirement.