I agree with the confusing names. Naming in the Java (and other language) ecosystem is usually bad. Here are some other classes that can be renamed in my opinion:
Instant: It is not instantaneous; it represent a period lasting a whole nanosecond. You can execute a couple to dozens of instructions in that “instant”.DateTime: What aboutTimestamp?
This is a silly reason: We should not improve because developers may have to adjust? I think having a Date & Time API with much clearer names can be a Kotling selling point.