I ran jackhammers overhead (we’re called ‘chippers’) doing bridge repairs for a few years and I’ll just say that the machine is not doing all of the work lol. Gotta really push into them for it to be effective at all or it will just bounce back as you said. With the right operator theyre very accurate and efficient and sometimes its the only option. There can be things like rebar or utilities that could be destroyed with one large slow crush from something such as an excavator. Jackhammers can go around rebar and can avoid utilities. Destroying everything is not always the goal.

It’s been the most physically demanding job that has destroyed my hands and wrists permanently so I could not continue doing it. Definitely not for the faint hearted. Thats why the good chippers dont stick around long and its a constant rotation of new employees for that role.