Why do many modern Hollywood films rely heavily on CGI and visual effects instead of actual sets? What is your opinion on this trend?

The “why” is quite simple:

So, I’m still not an expert, but at least I have a better understanding than most people. Do I care about opinions? Sure, But I can give a rat’s ass about the neighbor’s opinion, or the guy at the grocery store, or, for that matter yours. BUT. I would pay very, very close attention to an special effects expert working on movies, and what he has to say on the matter.

Some things are impossible to do with practical effects.

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There was a post here on Quora, where there were some question criticizing the special effects on Rogue One, and Moff Tarkin’s face. One of the guys who actually worked on the SFX Department for the movie answered. His answer was a master lesson on special effects. He took the job to explain the process, the challenges, the result, the technologies, all at great detail. After reading that, whomever got to bash the special effects must have gotten his tong shoved up his ass.

Opinions are like assholes. We all have one and they all stink.

What do you want to know? The why, or my opinion?

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Some other things are feasible, but much more expensive, dangerous, and with the same or worse results. And there are a few where practical effects work much better. So, whenever the cost is lower and the risk of hurting people is less, CGI effects are preferred.

Now, my opinion. Here it is:

Let’s go with both.

Why do people keep complaining about how some people copy and paste the question before answering it? To me, it's very disturbing and makes me want to block and mute them as annoying whiners.

Are you an expert in visual effects? Neither am I. Have you ever done any CGI animation? I do. I made a 3 minute clip back in 2006. It took me about 3 weeks. It was shit, but it was a great learning experience, Makes you respect all those people who do that for a living. So, whenever I listen to a schmuck saying “oh, now it’s so easy with computers”, all I can think about is “poor ignorant bastard… someone should tell him the brain is for thinking and the ass is for shitting before he opens his mouth again”.

My point is, my opinion on the matter, as yours, is irrelevant. The people who works on that field (my brother does) have a saying on the matter though. They can tell you with basis “these effects are great” or “these effects are shit”.