The film,
Bonnie and Clyde, had some issues for the family of real life Texas Ranger, Frank Hamer.
"In 1968, Hamer's widow and son sued the movie producers for defamation of character over his portrayal and were awarded an out-of-court settlement in 1971."
https://en.wikipedia.org/wiki/Bonnie_and_Clyde_(film)
It was not a flattering depiction of his character, and the film's huge success may have provided a monetary motivation for the family.
For all that, I think getting permission from survivors may be a bit much to expect. It could depend on just how historical the figures are. I would not expect you to track down descendants of Teddy Roosevelt, but a lesser known person might be a different matter. Another aspect to consider is if a descendant wants compensation in return.
I have avoided the issue by using fake historical figures instead. I am sometimes lazy about research and don't want to see if Ben Franklin was in a certain place at a certain time and then have to recreate his personality. I feel it overshadows the other characters to have such a "guest star" in the mix and it might not live up to a reader's expectations. This is especially true for a reader who is a Franklin expert. I have been urged to include historical figures in some books, but the most I'll do is a passing mention with no actual appearance.
But a WIP requires that I use a real scientist from the 1800s. He's pretty danged famous, but I'm still a "slacker." My solution: he has an assistant to talk with the protags. I get the name brand for science fans, but the freedom to run an original character in the scene.