Yikes. I spent 15 years developing native on both mobile and desktop. If you think that native has the same design flexibility as HTML/CSS, you're objectively wrong.
By design, each operation system limits you to their particular design language, and styling of components is hidden by the API making forward-compatible customisation impossible. There's no escaping that. And if you acknowledge that fact, you can't then claim native has the same design flexibility as HTML/CSS. If you don't acknowledge that fact, you're unhinged from reality.
There's pros and cons to the two approaches, of course. But that's not what's being debated here.