Well a few of those articles did say, (and i think the last link did specifically) that the place where the 30% drop would be the most likely (if happening at all) would be in theoretical scenarios (like Deep Learning, or Quantum Computing). Thats nothing the average user will do, and as such, such a performance loss shouldn't be happening/visible to the average user.
Pre-patch samsung magician results on my 850 EVO
Sequential
Read 550 / Write 522
Random (IOPS)
Read 95837 / Write 86596
Post patch:
Test 1: 543/117/84035/20422
Test 2: 546/135/77215/30640
seq read is pretty consistant, the rest is all over the place. I can't believe an SSD will have that much of a loss. From 86k to 20-30k
I'll have to contact samsung