EDIT
Silly me - I just assumed launching the HUB from terminal with the forced scaling wouldn’t work - but it does 
Hi all - in regards to HiDPI scaling - I can get the editor to look great when launching from terminal something like
GDK_SCALE=2 GDK_DPI_SCALE=0.5 ./Unity
But I’m not able to sign into the online services - it wants me to launch via the hub.
It would be great if we could modify the launch command the hub uses to get correct interface scaling - my tired old eyes can only squint for so long! haha