Because nothing can be perfect 100% of the time 
— if you would like to share the tracker and potentially what site it came from (if you know) we can try and see how it snuck through.
As it states on the site and has been stated several times before, it as temporary measure and will be changed/resolved as soon as we are able to.
You can go to brave://flags, search for a flag titled Enable download bubble and set the value to Disable and you will have the original download “shelf” from before
No, we haven’t
Have a wonderful day.