Technologically speaking, the impulse trigger is just a simple ERM motor, it doesn't do subtle, it does on and off vibrations. They can lower the speed to simulate low vibration but that's about it. Most of the other "pop" gear shift and traction feedback is our brain playing tricks on us. Most tactile and haptics tech exploit our brain to fill in the blanks where there is nothing. It was a genuine brilliant idea to add miniature ERM motors in the trigger housing.
The DualSense can simulate different sensations using the exact same motor but applied differently.
Spring Sensation by applying slight force opposite to the already tensioned trigger but not stopping the movement, it moves with the trigger pull.
Vibration by driving the gear up and down and it can be subtle or damn near violent.
The Pop sensation, the mechanism removes tension briefly and pushes back at you giving your finger the pop feeling of gear shift, same mechanic can be used for gun trigger pop feel as well. Our brain does a lot of heavy lifting.