When I has my 1st budgie (Ash) he was so well tamed that he would Stan on my elbow enjoying the ride while I brushed my teeth... I would say he was super tamed and we bonded extremely well.
Where Jay Is only finger tamed at the moment but that's only while I hold a mirror... I have thought the same thing. We haven't fully bonded but there are good days and bad days so it isn't easy to tell.
There are signs to look for but I think it's something only the budgie and the owner will know
“The man who asks a question is a fool for a minute, the man who does not ask is a fool for life.” - Confucius