Fitbit Charge 6 supports Google Fast Pairing, but not Google Find My Device ?

[Teraya]

Fitbit Charge 6 supports Google Fast Pairing, but doesn't save the device to the Google account for use with the Google "Find My Device" network. 

Update/Clarification (AUG 4th 2024): 
Forgive me, I may not have been clear.  I was hoping someone might elaborate on the "why" aspect of this. 
I am curious if this is a bug and is not the expected behavior (in which case I can try to submit/report it as such),
OR if maybe it is actually by design and is the expected behavior (in which case I hope to find some explanation of the reasons behind the design decision, so I may understand it better). 

[Rich_Laue]

Yes, you are correct.