The hard thing is making large sheets and single layer. Multi-layer and small sheets is pretty easy. Too many sheets, and you have graphite though. But those small chunks have some useful properties (same with CNTs, which you can make with a detonation). Also, realize that they don't have 0 resistance (which is a superconductor), read as "it creates heat". This limits the amount of current that you can drive through it. So there's still a lot of problems that need to be solved. But there are definitely huge interests in also looking at using it for filtering molecules. But this is also difficult to do with precision. And that's the root of the problem, precision and consistency. I know that doesn't exactly answer your question, but all I can say is that it feels like we are close.

This is how everything is. It takes years to build up enough experience with something new to learn what it's capable of, it takes more years to learn how to build interesting stuff with it, more years to learn how to adapt manufacturing processes at industrial scales, more years for real products to hit the market, and more years for those product designs to mature and actually reach enough of their potential to be a worthwhile upgrade to "the old way of doing things".

It took almost a century for electric cars to get good, it took almost half a century for reusable rockets to become practical and cost effective, it took decades for lasers to become ubiquitous, it took decades for the internet to mature into a part of daily life, etc, etc, etc.

Industrial scale production of graphene is still the most challenging area in anything graphene-related. Currently, the are several techniques for large-scale production but nothing large enough that can fit the supply chain of mass-produced goods like batteries.

If pigs could fly, their wings would be made of graphene.

Good question. I'm eager too. I've been able to buy Graphene Concrete Admixture and graphene-infused PLA filament for my 3D printer though.