Why does commedia dell'arte continue to impact modern theater?

Commedia dell'arte has had a strong impact on modern theater and continues to be important today.
Improvisation is one key aspect that, many would argue, has even gained in importance. It can be seen in general in all improvisational comedy and specifically in influential shows such as Saturday Night Live.
In early twentieth-century British music hall and American vaudeville, the incorporation of music numbers into a comedic frame, the inclusion of stock characters, and the use of physical comedy or slapstick all owe a debt to the earlier Italian form.
The character of Pierrot has been featured in mime acts and adapted as Marcel Marceau's poignant Bip the Clown. He influenced Charlie Chaplin's Little Tramp as well.
Modern playwrights as well, notably Samuel Beckett, have drawn on the form. It was a strong influence on the Theatre of the Absurd.
Going back to earlier modern times, Shakespeare drew liberally from its conventions in his comedies —both in those set in Italy and in the silly plays-within-plays he often inserts into his works.
Today's interpretations of Shakespeare and other classics may expand on commedia elements, such as One Man, Two Guvnors, based on the eighteenth-century A Servant of Two Masters, which in turn had interpreted commedia dell'arte in England.
http://www.shakespearetheatre.org/watch-listen/a-well-made-comedy-the-legacy-of-commedia-dellarte-carlo-goldoni/

https://www.britannica.com/art/commedia-dellarte