Of course, we need government action! But do you know the micro plastic content coming from tap water? Do you have much of a choice as to what you are consuming? Wouldn’t you want to filter it out?
As far as technology, this isn’t pie in the sky, it seems fairly simple and I wouldn’t be surprised if home-made solar punk versions start appearing in zines and online forums.
Why not just have our local municipal water supplies filter out the micro-plastics why is drinking water an individual problem that each household has to solve themselves?
Getting microplastic out of the water is important.
But in the long run that's not the solution. Microplastic is not just in the water, but everywhere, like in the soil. Textiles not only shed plastic when you wash them, but even more when you wear them. Solution: don't buy. Use natural fibres.
Same with plastic utensils, cups, plates, containers etc.: don't use! There have been alternatives for (almost) as long as humans exist. From wood to metal to ceramics to glass.