export PLASMA_USE_QT_SCALING=1 no longer works

I’m trying to get the scaling right on my 4k monitors, but icons look wonky, and the whole thing doesn’t look right. I used to just throw export PLASMA_USE_QT_SCALING=1 in /etc/environment or ~/profile, log out and log back in, and I’m good, but now this doesn’t do anything. I can’t be on wayland 100% since not...