A 25% retention rate is pretty good compared to the 4000 years of culture that preceded it. Who was the best King Lear in 1842? What made their performance special?
There's actually a surprising amount of information about famous stage actors, even going back to the 17th century. There are quite a few written accounts describing specific details of the staging, casts etc.
To answer your question, Samuel Phelps seems to have been the most popular King Lear of that time period. Prior to him, possibly Edmund Kean.
By the same token though, we also have written records of the lost silent films.
Who would have watched them again? A few weirdos and only a tiny random subset chosen by random criteria. Might as well watch the 25% that was preserved and is waay too high anyway.
Some things must just go away.
Silent movies.