I'm facing the issue too.
DxDiag attached.
I powered through this bug aswell, Sometime around the asari secretary is when it started to resolve itself.
Thing is i think its area oriented. When i was slapped with the bug i backpedaled through the complex and headed over to clear a part of the start of the facility i hadn't done yet.
When i got to the dead end the framerate was normal again. So, i got back on track and when i reached the area above the cells with the salarians the bug was back.
Powered through it to Rana Thanoptis (asari secretary) and it started fixing itself again the further away i got from the salarian cells
