[alexmcc81]

They don't even need to switch to Plasma. KDE is build on libraries [1] that build on Qt. You can build a custom desktop environment like LXQt [1] from them.

[1] https://develop.kde.org/products/frameworks/

[2] https://en.wikipedia.org/wiki/LXQt#/media/File:LXQt_0.10_-_A...