It seems to me that we paused in killing them off so rapidly from ~10,000 years ago when we stopped spreading around the world (there were a few stragglers, but the bulk of them were gone by then) to ~19th century when industrialization and globalization started letting us destroy all habitats everywhere.

Just that classic mid-project dip in motivation, once you've picked all the low-hanging fruit.

Not that much longer. This mass extinction is believed to be 10-100 times faster than any previous.