Yes, that's right. No, you really cannot trust anything you see on the Internet. Take a listen.
No microphones or movie cameras existed yet in 1862. But no matter. The technology today for doctoring old footage is still rough. It's easy to spot a fake like this, and watching Lincoln's lips move along with the voice is creepy. But over time, this software will improve and "reality" some day may become like just another flavor of ice cream or another type of TV show.
Beware, my historian friends. If Abe Lincoln can look at you in the eye and speak convincingly in what appears like his own voice and his own words, then how much weight will our skeptical, academic, scholarly works continue to carry in comparison?