The difference between Sci-fi and Fantasy

I will always see him as Agent Smith. Always. Even in things he was in before he ever played the Agent Smith role.

He'll always be Tick to me, the fabulous single dad from Priscilla.
- Same here. I love that he blew up career-wise after that, but he was already an icon in my world!
- He is one seriously incredible actor.
Wasn't the Matrix his break out role? (I tracked down a short he did, it was ok.)
- Yeah, but then he was in things like LOTR - and it broke my immersion. I was like "wtf Agent Smith made it to the other franchises! He's spreading!"
- In the West, yes. He's known in Australia.
Same. It's actually a thing that happens to some actors who got really famous because of a specific blockbuster and other directors don't want them because it would break the viewer's immersion. Daisy Ridley spoke about how for some time after her Star Wars role, she didn't get nearly as many offers as she expected.

In Cloud Atlas he played the female, middle-aged, sadistic matron of a care home that imprisons it's residents. Honestly, ¹⁰/₁₀ movie just for that.

He also played a Cajun devil in the post apocalypse
- And a prototype version of Agent Smith in the 1960s.

Presenting the Desert Eagle as a practical sidearm is deep fantasy.

Isn't there a non .50cal version
- Yes...and it's not much better....357 still kicks like a bitch.
  
  Source, I have said .357 DE and it collects dust and only comes out when someone wants to fire it. It's boring and a complete waste of money as a firearm, but it's a collection piece.
Agents can punch through a brick wall.

What then is him in Priscilla or Cloud Atlas?

a goddess
- "The Dressmaker" Hugo approves.

And "family film" is when he looks like this

Me on Monday VS me on Saturday

WHOA your hair grows really fast

In both cases he looks like a disappointed dad. "Why aren't you more like your brother?"... "When I was your age"... "Stop playing with your friend Morphius"... "Don't you dare put on that ring!", yatta yatta yatta.

Dad, it's all a simulation!

What is it when Hugo Weaving looks like Guy Fawkes?

It's the 5th of November.
What is it when he looks like a tall blonde woman with a sparkly dress, a massive flowery wig,and a strong jawline?
- Majestic.

Science fiction is a subset of fantasy. Fantasy is any work in which the setting is deliberately made different from the real world. Science fiction is when those differences are due to the presence of advanced science and/or technology.

No, Sci-Fi and Fantasy are two distinct subsets of Speculative Fiction. Another would be Supernatural Horror.
Counterpoint: Science fiction is fiction which shows a world different from our own, but different due to changes in culture or technology that plausibly could take place within our own universe, whereas the differences in fantasy are ones that are fundamentally incompatible with the known physical laws of our own universe.

Edit: How sharp of a division one wants to make out of that "plausibly could" clause is the dividing line between hard and soft scifi.
- This is a great definition. There's a lot of "sci Fi" that is much more firmly in the realm of fantasy (I say this as someone who kinda likes Dr Who). Being in space is not enough IMO to be called sci Fi.
What about sci-fi that's literally only different from the real world because of fictional technology? That makes up a bulk of the kind of sci-fi I am into. Cyberpunk and the like.

Star Trek technically takes place in the actual universe. Is it fantasy because it's almost never on Earth?
- The genre is usually divided into "soft" and "hard" fantasy.
  
  Cyberpunk is generally considered hard fantasy, as is stuff like The Expanse or Interstellar.
  
  Star Wars is unabashedly soft SciFi, it's a straight Fantasy story in space.
  
  Star Trek is a half-breed - it pays some lip service to scientific "plausibility", but much of it stretches that envelope beyond the breaking point. Scientific accuracy was never the point of the series to begin with.