How dangerous stunts were shot by Charlie Chaplin

Real movie magic.

And then there’s Buster Keaton who actually let the side of a house fall around him and actually jumped on a moving train. No camera tricks

This is incredibly smart given the technology that was available at the time. It's basically the same as as CGI, but the tools to generate an image have been updated.
And somewhere between this and CGI people edited the actual film, I believe this was done to create the lightsabre in the old Star Wars movies.

Sure they used tricks like this but they also didn't have a concept of a stunt double. He did plenty of things that would have resulted in his rather painful death if something went wrong.