The advantages of green screen are limitless. Green screen allows filmmakers to do almost anything so long as they put in the work to ensure they get it right. The biggest advantages of using a green screen are:
It allows for exciting and otherwise-impossible scenes to be produced, expanding film making possibilities and language.
It can protect actors by keeping them in the studio and away from the dangerous environments depicted using green screen technology.
It can allow actors to appear on screen together even if they film the scene separately. This helps when scheduling is a concern.
Disadvantages of Green Screen?
Green screen use is difficult and also presents some considerable disadvantages. These include:
If the lighting is not perfectly balanced, the technique appears artificial and off-putting for audiences.
Despite being cheaper than the real world alternatives, the process is nonetheless expensive, time-consuming, and cumbersome and thus not ideally suited for a low-budget or independent film.
If the foreground footage contains any bit of the background color, it will be replaced during the keying process.
I think that green screen have more advantages that not. Because green screen like here https://greenscreenstock.com/ helped me a lot with my photoshopping of background