You don't need metamaterials. There are various patents on "invisibility cloak" systems, and most of them use screens and cameras to project what's behind the wearer onto the front-facing screen, e.g.: https://patents.google.com/patent/WO2016160588A1
Some others, mostly intended for military vehicles, aim to match surface IR emissions to the background.
Using metamaterials -- which need to be printed or, even worse, made with lithography techniques -- adds unnecessary cost and vastly increases complexity.
Screens have a very limited range of brightness. More importantly, they only project a picture in one direction, so, if you can move laterally, you'll notice that it's a flat picture.
If metamaterials can alleviate any of that to some degree, they could make a form of invisibility cloak covering large objects practical.
Agree, both screens and metamaterials for this application have their pros and cons. Manufacturing metamaterials at a large scale is an area I'm looking into next!