Hard same on the frame-dropping, only started on hotfix 1.11. I work in gaming, specifically with build testing, and decided to go hard on figuring out what could be messing me up.
I have a rig with an i9-9900K @ 4.79 GHz, 64 GB of RAM @ 3200 MHz, RTX 2070 Super that was running between 60-70 FPS with settings on High/Ultra, 2160x1440, and with DLSS on Quality since launch. I updated to driver 461.40 on the 26th, before the 1.11 patch drop, and had the same performance. Now, once I breach protocol, I drop to about half my framerate. If I just quickhack something or someone, I drop to between 10-12 FPS.
Even running NOTHING in the background -- no browsers, no BG apps, no nothing outside of Steam and Task manager for watching what was being utilized-- will improve performance on settings that I know had been running just fine prior. For a wild hair-up-my-butt experiment, I decided on even lowering settings and testing again. Medium preset, keeping resolution the same. After a quickhack, I drop from between 65-70 FPS to 33-38 FPS. Low preset, same resolution, same quickhack/breach protocol process, dropped from approximately 71-80 FPS in a room, to 20-30 FPS.
It's unfortunate as hell, since the game is utterly unplayable with this much slowdown. Hopefully this is fixed in the next hotfix.