Reproduction steps:
1. Open my attached project ("case_873297-repro")
2. Open the "main" scene
3. Select the "Reverb Zone" in the hierarchy
4. Try to change the "Room Roll off Factor" in the editor

Result 1: It doesn't change

5. Try to change the "Room Roll off Factor" in the "Test" component

Result 2: This time it changes

Reproducible on: 5.3.7p1, 5.4.4p1, 5.5.f1, 5.6.0b5

Tested on Windows 10