my iswara is the older full spec auto, so it had very close to 1 ton (the original paper sheet kerb weight was over 900kg ady iinm), not to mention subwoofer and sound proofing and lotsa stupid snake worm bars.
regardless, it still isn't a 1280+driver 1360 kg inspira no doubt.
and the more speed it carries, the more momentum additional weight will affect.
well that's what RCS is been telling me for my dampers, overall it's the combination of the tires and dampers. if i want to run these tires, i need harder dampers to push the tires to the ground more to deal with road imperfections.
to give an idea, softer tires (particularly sidewall) can deform to road imperfections (lets use a rock as an example), and stay firm on the ground. harder tires like these ad08r has steel plate reinforcement on the sidewall to make it very damn stiff, road imperfections will cause it to "bounce/hop" off from the road and when that happens, that's good bye to grip/traction already, even if it's only for a split second.
not to mention, if it isn't pushed to the ground hard enough, there will be a point where the weight shift/damper rebound will exceed the softer dampers limitations, while you may not realize it as you're having a false sense of grip due to the much grippier r spec compounds the ad08r offers.
it'll be a dangerous situation where you're still having firm grip and then out of a sudden your car is sliding non stop.
you'll probably never see such situation happen in my videos as i have stability control system to limit the car's power/correct any traction lost via braking modulation. However the screeches despite "not so fast" cornering speed (definitely something the ad08r by right should EASILY handle) should be a dead giveaway.
tldr/summary/lesson learned: soft or hard dampers, coilovers with extremely stiff springs, extreme tires (like the ad08r) or semi slicks, you'll need a good overall combination to make things work and not simply dumping the best/most expensive piece and expect miracles to happen.

I understand your take on this.
Unfortunately, not knowing how your Inspira was set up, kind of hard to guess. I think the issue lies something other than just the damper/spring settings. The key element here is we still do not know what sort of steering angle you had to input when it washed wide.
Im going to throw in another spanner. Most wont realise it but how your front behaves sometime depend on a lot of that the rears do. Maybe you are looking at the wrong end of the car. Food for thought.