Ten percent of the big fish still remain. There are still some blue whales. There are still some krill in Antarctica. There are a few oysters in Chesapeake Bay. Half the coral reefs are still in pretty good shape a jeweled belt around the middle of the planet. There's still time but not a lot to turn things around.
It's hard now to imagine that kind of travel and the daily tasks they simply took for granted. If a wagon axle broke you had to stop and carve a new one. To cross a river you sometimes had to build a raft.