Following the thread for a while now and i think we have to differentiate between two kinds of performance bugs here. On one side we have users with degrading fps since the last few updates, and on the other hand we have users with degrading performance caused by high cpu-load. Reducing graphic-settings may help if you count yourself to the first category, but not if you belong to the second one. Furthermore, if your cpu is saturated (main-thread / render-thread) you may lose fps as well, simply because the cpu cannot shovel the data fast enough to your graphicscard.
In my personal case i can say, that fiddling around with graphics settings wouldn't change anything. Simply because my 6900XT is idling around and the frametimes are skyhigh because the cpu-load on one core is maxed out (using MT by the way, but one core is ALWAYS saturated after some time into the mission in SP, depends on the number of active units), whatever DCS is doing on this one.
Additional it's not only the game itself, that kind of performance problem also happens on the dedicated server, which doesn't have any rendering to do at all.
And... im pretty sure to say, it has something to do with groundunits in particular. I have a mission i was playing with some friends that worked for months without problems, and that was fine with 2.9.5. Now at 2.9.7 even the dedicated server starts crashing ~1h into the mission because the cpu-load on one core is so high, that the server is completely unresponsive. In the past the mission could handle ~900 groundunits without problems, now it struggles with something like ~300. And yes i know, the dedicated server is ST, but that single thread is not supposed to set it's corresponding cpu core permanent to 100% - at least, it was not in the past.
