Whales and bison were subject to very modern techniques. While sailing whalers did stress whale populations, it was the steam launch and exploding harpoon that

Whales and bison were subject to very modern techniques. While sailing whalers did stress whale populations, it was the steam launch and exploding harpoon that really did the whales in. Bison were destroyed with rifles, which are new in themselves, but the mass-slaughter behavior was enabled by rail transport. Plus they were plenty stressed by competition with cattle, bred for rail transport, and enclosure of the prairie by barbed wire. Earlier lithic-technology subsistence whale and bison hunting doesn't seem to have been a big problem for either. I won't say that early human hunting didn't contribute to or cause mega-fauna extinctions (in fact, it seems quite likely) but that's not highly analogous to these more recent events.