Ride quality - specific observation

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UX 300h F Sport Design with Bridgestone Alenza RFTs, tire pressure lowered based on advise from this forum. Also was told that F Sport Design has a normal suspension, Sport is just a name.

Let me explain what I am trying to achieve. I think in general ride quality can be described by these two components:

1. High frequency, low amplitude vibration when driving on a flat surface that does not have potholes or bumps. In a car with a stiff suspension or low profile tires you get that a lot.

2. Jumping over bumps. This is when you drive over a pothole or a bump. 

My observation:

First component - no issues, the ride is smooth, no vibration.

Second component - the UX jumps too hard, especially when both rear wheels go over the bump at the same time.

I noticed that many cars do the same, for example, MB GLA, B-class. On a flat surface the ride is smooth, feels heavy and expensive but once you hit a bump or a pothole it just jumps too hard.

Hoping that the run flats are the reason.