Kudos for posting something clear and concise. It sure would nice if other posts included this level of detail.
Unfortunately, everything you’re experiencing as well as the remedy you’re using with respect to X-Y compensation is exactly how the slicer works. If it’s any consolation, you’re doing all the right things.
The issue is not the printer or the software, it’s simply that results will vary widely based on filament type, moisture in the filament and filament parameters.
On your last note however, I think you may be presuming that calibration at the factory is possible between filaments. As stated above, the laws of physics just make this impossible without extensive sensor technology to provide real time compensation for filament shrinkage/expansion. It just isn’t available yet in Consumer 3D printers just yet. Maybe some day, but not today. The X1 tries to do this with LIDAR. How’s that been working out? 
According to many X1 user posts, not very good I’m afraid.
I think you’ll find that X-Y compensation works just fine. I might suggest Orca Slicer rather than Bambu Studio because it has baked-in calibration tools that really work nicely once you get the hang of it.
There was a lengthy thread on this topic that you may want to look at. In this case, it was the challenges of getting 3d printed threaded objects to mate. But the issues are the same regarding intermateability between two parts and calibration of each filament.