Flexbox support in QML[1]. Plus, there are some wrappers that make seamless transition between desktop and mobile view like MauiKit[2] and Kirigami[3]. I don't think they're perfect or that they are doing it correctly even, but they're onto something with their main approach.

[1] https://github.com/tripolskypetr/qml-flexbox

[2] https://mauikit.org/

[3] https://develop.kde.org/frameworks/kirigami//