[ClikeX]

For modern movies, where you likely need to adjust some things in the scene using CGI, it is much easier to just add VFX to a pristine 4k image and then deep fry it with something like this.

As for your second point. A friend of mine's little sister asked him for help setting up the vintage camera she bought. And it was an early 00s digital point & shoot.

[danaris]

And if you want to give a really unsettling effect, you could first apply a filter like this, then add some crisp CG on top of it.

Give the idea that this is something from another reality.