The viewing angle of the screen is definitely NOT under firmware control so I'm not sure what you are getting at.
I usually position my scope so that I'm looking directly at it. My guess is that the designers of the display had the same idea
Of the two images you show, to me the more direct view you show looks 100% better.
Yes, there is no view polarization option.
Here my screen shots as how C1 RMS level changes
1) after previous day with 3 times Self calibrations
2) have C1..C3 on GND and C4 NOT
3) changed C4 to GND. To me this is completely odd and looks buggy.
BTW: LeCroy simple do a re-calibration even changing some settings.
4) C1..C4 and mixed with FFT:
- Nice, dependent of channel selection, text gets its related channel color.
- But gets soon unreadable as text has no cleared background color as here black.
- Same issue as on FFT text: text should have a cleared background color.