[weego]

You're also only going to get any of the perceived benefits of the choice to build a custom UI kit if you're only solving the same problems that the framework authors were solving.

If you suddenly need, as an example that I've come across, a list of stats to update with a high tick rate which is unusual in an app so no one optimises for it you'll likely find you're no longer anywhere near a native experience.

I know that's not a unique problem with opinionated frameworks, but it's usually a programming issue to solve in the background, not a deal-breaker due to how every customer suffers.