I think this would be a nice feature.
I couldn’t find an already posted feature request: https://bugs.kde.org/
Feel free to open one.
Will later releases add this ability to Plasma?
Maybe if someone report the feature request as a start.
Does someone (like myself) need to organize sponsored work to see if Latte Dock could be ported to Plasma 6?
You can offer some sponsoring, but the thing is the original author of latte dock withdrew with good reasons (psifidotos: Latte Dock | Farewell...). And no-one else within the community has strong knowledge about latte because it was mainly a one-man project (Bus factor - Wikipedia). Unless someone decide to put some real effort in helping the situation that won’t happen, knowing our transition to Wayland is I believe would make things harder.