AI enhanced deep fakes get better and better. Slapping some low video quality and compression artifacts on it, some poor lighting, etc. and it could easily pass.

It's not like CGI in movies, where they are doing it in controlled, well lit sets in high definition camera quality.

Plus, we see it constantly -- development companies, both video games and movies, are full of low work ethic union workers who are afraid of a little crunch time. Third parties almost always do the work better nowadays.

You can hide the uncanny valley of Hollywood with a few tricks that aren't suitable for the big screen, but are for "found footage" or "hidden cam".

Also re: "multi million dollar movies"

Keep in mind we already know a lot of those dollars end up being laundered through overpriced stuff in order for executives to pocket as much of the revenue as possible without paying royalties from profits.