As of 5.5, it only edits the selected keyframes if you select more than one keyframe. The text also turns yellow in this case to indicate that you’re editing more than one keyframe.
Here’s some examples to show what I mean. In the following screenshot, the behavior of editing the current time even if you have a keyframe selected is back to how it was before. If you edit the value here, it will edit the keyframe at frame 15 even though you have the keyframe at frame 30 selected:
When you have 2 keyframes selected, you’ll see the yellow text which indicates it will edit both selected keyframes at frame 15 and frame 30:
