Man that really sucks.

I'm guessing that it's not reasonable to get the guy to chill or get the builsing tuned up so that it doesn't transmit so much vibration.

The "ideal" wouls be a platform that can move laterally (and a little vertically) but that damps the vibration. Imagine a platform the bed sits on, but with springs below it. Or something fancier that acts like a spring but uses another mechanism. This way, the bed will move less initially (the floor will move and the bed will have to "catch up" based on the weaker + delayed pull of the spring) ans be damped.

Keep in mind that I haven't tested any of this, but here are a couple ideas.

1. Casters/rollers, each of them on a little square (maybe silicon?) that keeps them from rolling too far. This will have weak lateral damping ans probably zero vertical. Imagine something like this but you actually buy one larger than specified so it can still move a bit: https://www.amazon.com/Yupeak-Bed-Stopper-Furniture-Pack%EF%BC%88Black%EF%BC%89/dp/B07MPR999F/

2. Put a box spring under your mattress and literally attach springs on the bottom and sides so that it only contacts your bed frame / floor (not sure what your setup is) via springs. Strong springs so that they don't bottom out when you lay on the bed but not so strong that they don't damp enough. Probably bed springs, basically.

3. A second soft mattress to put under your mattress. It's basically just a set of springs and is already the right size. This is probably the best option.

Also, if your bed is next to the wall, move it 2-3 inches away from it.

Hope this helps!