There doesnt seem to be a way to change the size of text in HB for 2020. Holding CTRL and scrolling the mouse wheel doesnt do anything anymore, not sure if this is just something that hasnt been implemented yet or if its not possible.
Within the client file you should be able to change the Zoom %, with a client file open, top menu bar View > Magnify all forms and choose a percentage.
@Orlando is the HB text size adjustment on anyone's radar yet? or can it even be done with this new format?