I haven't played much since the update until today. Did a fair bit of trading in my Conda but didn't get interdicted too many times and none of them were too much of a threat except for maybe 1 lawless Anaconda which took down 1 ring of my shields pretty quick with some heat weapons but I was preparing to dock so wasn't in too much danger. If it happened in the middle of nowhere maybe but I also might have had enough time to get away.
Also did some mission running out of Aditi in my Python. Just regular cargo no smuggling. All missions were Tycoon or lower. There was one elite mission but I avoided that just to see what the NPC's would be like with the other missions. Was only interdicted once or twice over 20 jumps on the way back.
I was expecting things to be a lot worse from what I have heard but it wasn't bad at all. So maybe some RNG is involved with interdictions? I don't know.
Were you playing in solo/group/open? This might also be a factor. Also if you stay long periods milking the same trade route this might also cause more interdictions the longer you stay in the same systems.