I've been using LXQt for some time now (years), and with Today's Arch upgrade, which included a LXQt upgrade 0.17.0-1 -> 1.0.0-1, everything was showing app really big, from LXQt own text (menus, icons, widgets, etc) to other apps. The only work around I found was to reduce the font size on LXQt's preferences, and also on Qterminal, I had to change it from like 18 to 10 on Qterminal, and from 16 to 10 on LXQt itself. I still see other apps bigger than what they used to be, and in particular the apps' toolbar became wider, and the border surrounding Qt apps became wider (to the point it's annoying).
It's not about manipulating QT_SCALE_FACTOR + QT_AUTO_SCREEN_SCALE_FACTOR, and the like, because that's to make things bigger when they look way to small and unreadable. Actually by setting QT_SCALE_FACTOR to 1, its the same behavior as not setting any variable, and lower than 0 values don't really work on Qt (I tried, and the results are really weird, non functional to say the least).
Have other lxqt users experienced the same on Arch? Would it be an Arch building and packaging issue? Or this is totally an upstream thing?