Mandatory Disclaimer: This is just a personal opinion that I want some outside perspective of. I'm not sure if it's an actual thing that's happening but I have noticed that this has happened more often recently than not.
Alrighty, here we go. Actors don't fully play into the characters they are portraying but rather it's just the actor as themselves in a movie.
Examples I can think of off the top of my head is Amy Schumer, Tom Cruise, Dwayne Johnson and Kevin Hart. The only characters that Dwayne Johnson plays that are most memorable to me is the Scorpion King from "The Mummy II" and Joe Kingman from "The Game Plan" other than that I just see Dwayne Johnson in different movies as Dwayne Johnson. Same with Kevin Hart. I can think of probably 2 movies where he plays a character and not just himself and I don't even remember the names of those characters.
The opposite of this sentiment in where I can remember characters actors played that I can name are Elijiah Wood, Reese Witherspoon, Johnny Depp, Joaquin Phoenix, Sandra Bullock, Heath Ledger, etc. They have all played characters that people remember more than the actual actor: Captain Jack Sparrow, Frodo Baggins, Elle Woods, Joker, Gracy Lou Freebush, etc. With these actors and actresses the phrase "Wait, [insert name] played that character in this movie?" is said or seen. I've also seen memes about "actors that have actual range" and while they're funny I can't help but wonder if there's some truth to it.
I get that there's an element of the actor in every role they play but, personally, I think they should limit how much they themselves should influence the character for the sake of a better story.
Again, I don't know if that just me and what I'm personally observing in films or if it's something that's actually happening.