I have noticed the new trend of putting a big stack of blocks under the jacks/stabilizers but do not understand it. With the wheels chocked to stop front to back movement the stabilizers just do up and down or bounce. For us the X chocks have made a big difference in front to back movement. I also run my stabilizers all the way down unless we are on grass than I use a board. Maybe you could try a set of the old style jacks
https://www.amazon.com/RVGUARD-Trailer-Stabilizing-Adjustable-inches/dp/B083KJ782P?th=1.
Back in the old days we used them before they had the crank down scissors jacks / stabilizers. In fact the first scissor jacks I used were from a car from the junk yard. My uncle welded a mounting plate on then but they were real jacks.