It is a good question. I can't tell you which is better than the other. Laravel is a good framework. Currently Laravel will be a good choice since it has a big ecosphere and support.
We create Windwalker just because we want a high performance framework with a bundle system like Symfony, we don't love too many static Facades in Laravel. And we all familiar to Joomla style for a long time.
I believe developers will choose what they like or familiar to, not for the one which is more powerful.
And you can also consider Windwalker packages if you think it is useful, for example, if you want to use Blade out of Laravel, Windwalker Renderer will help you:
https://github.com/ventoviro/windwalker-renderer