About a week from now, we can celebrate public domain day again. In USA, works (except from recorded music) published and released in 1924 will become public domain in 2020, and works from 1925 will enter public domain in 2021, and so on (thanks to Bill Clinton signing the Sonny Bono Act in 1998). Novels, paintings and movies will become available for everybody, no matter when the creators died.
In Europe and other places in the world, it is irrelevant when something was released. The only thing that matters is when the creators died. Once 70 years have passed, everything they made ends up in public domain. With a few exceptions, like Antoine de Saint-Exupéry's story The Little Prince if you live in France, or J.M. Barrie's Peter Pan if you live in England (for previously unpublished material, those who publish it first will have the rights for 20 years before they enter the public domain).
For instance the works of Edgar Rice Burroughs. Much of what he wrote has been in public domain for years in USA, but never in Europe. In 2021, everything he wrote will become available for Europe. I assume that include making merchandise based on Tarzan and John Carter. In USA, those rights still belongs to Edgar Rice Burroughs Estate.
So there are both advantages and disadvantages.