Degenerated signal at a logic level converter
5V CMOS logic is approx 50 Ohms not approx 50k.  Your Digital level shifter is pulling up (attenuating) Ro to 5V with 10k.  So your response is as expected.
To make 0 to 5V via 47k down 0 to 2.5V (which ought to work for 3.3V logic) requires a 47k load to ground ONLY. You can always do something different to get 3.2V.
By replacing the level shifter and invert the signal with 5V to 0V and 0V inverted with pullup to 3.3 by;

using any transistor BJT or FET as a switch.