If this issue of power or range reduction is of interest, I suggest reading the linked thread and drawing your own conclusions. Two observations / comments:
1. "P60D" is an exaggeration of the results that were reported in that thread. A number of owners reported loss of up to 30 rated miles, which is not anywhere near close to the original difference in range between cars with the original 85 and 60 packs (the difference is somewhere around 50-60 miles rated). That's a bad thing to have happen, but don't make it sound worse than it is. (Don't take my word, you can read the thread for yourself.)
2. Obviously people in that thread will be reporting cases where they updated to 2019.16.x and lost range. You won't find a lot from people saying they updated without incident, because those owners have less reason to post anything (and in fact may not even be aware this problem could exist). For the record, nothing notable happened to the range on my S85D when I updated. Obviously it completely sucks for those people who lost range or power. But one can't conclude from that thread how widespread the problem is, why some cars are affected and not others, or how likely someone is to see reduced power or range on any given P85D+.
There definitely appears to be a problem, but there are still several important unknowns about it, and it might be more nuanced than some comments might make it appear.
Peace,
Bruce.