Have you seen my very recent thread about my car?
https://www.volvoforums.org.uk/showthread.php?t=316370
To recap, mine was
exactly like you describe - crashing over bumps, but fine on a good road, and no apparent handling issues. Mine appeared to pass the bounce test OK.
New Sachs shocks have vastly improved it (installed at 137k). I last wrote in that thread at the start of the week after only 500 miles on the new shocks; I've been a fair bit further now and I'm so glad I had them changed. Like you, my garage doesn't seem to be too interested in preventative maintenance, and told me they've seen cars come in on 200k on the originals and seemed a bit surprised when I said I wanted them to replace the shocks which were in good visual condition.
I won't rewrite everything I put in my thread, but to summarise the change, the crashiness is gone, road noise has quietened down, feels more stable. No longer thudding over surface imperfections, drain covers, potholes, speed bumps and rumble strips.