You can presumably buy a different brand of flour or find a different source quite easily? Same applies to most other “fortified” products. With water your’e basically forced to waste money on bottled water or very expensive filtration systems.
But yes, adding additional vitamins or minerals to food products is generally unnecessary when supplements are generally cheap and highly available these days.
The knowledge about the supplements we need also cheap and highly available and yet lots of people don't have it. I myself don't know all the supplements I need.
I feel like for better or worse we are being forced into an era of individual responsibilities where the safeguards that we used to rely on without having to think are being actively dismantled.
But yes, adding additional vitamins or minerals to food products is generally unnecessary when supplements are generally cheap and highly available these days.