De Niro is great.
All the actors and actresses mentioned here are legends.
Watching Joachin Phoenix in Joker, though, put him on my personal favorites list. That was an amazing performance. It takes great talent to make the audience both be empathetic and repulsed by a character at the same time. A lot of that is writing, but without an actor to deliver the performance perfectly like he did, it would've been lost.
Another great film I enjoyed was The Irishman. Acting was on-par for all the greats; De Niro, Pachino, Pesche, etc. But it was great.
I think by far my favorite actors of all time, though, were Henry Fonda and Gary Cooper. Both are consummate orators.
Check out this clip from The Fountainhead. Hard to beat a monologue like this.
https://www.youtube.com/watch?v=AX4MKIDvXLM