They exist. My last home before my free-standing house was a poured concrete and brick condo. You could jump up and down with an elephant and the downstairs neighbors wouldn’t hear you.
You just have to test before purchasing. And, of course, this costs more.
Mind if I ask how you go about testing this? Seems like you would either need access to multiple adjacent units at once (which seems rare unless the building is new), or you’d have to go by the construction type but that isn’t really a “test” so I assume you meant something else.
I was friends with my neighbors. I didn’t literally test with an elephant but I was morbidly obese at the time and did quite a bit of jumping and furniture moving.
Joking aside, I would ask the inspector to test the building materials and widths of floors and ceilings. I assume there’s some standard performance that if you have 4 inches of concrete that’s bad but 12 inches is ok, or something like that.
When I bought my unit, I didn’t use an inspector but did talk to neighbors and my realtor had worked on multiple purchases in the building and had those accounts.
You just have to test before purchasing. And, of course, this costs more.