It’s not just the tooltips. They changed a lot with the UI. Including scaling.
ATC pop out window used to scale text nicely on my 2nd monitor.
Since SU5 I need to scale the whole UI to a point it’s hard to read in order to keep the ATC window small enough to be usable on that 2nd monitor…and even then it’s all still a bit janky.
The airport search and value input in world map also…much less user friendly after SU5 (unless you navigate with gamepad rather than a mouse?)