Active balancing is good for the brain. One could still use a hand on a post, counter, chair or some such to facilitate balance training. There are foam pads, which when you stand on them don't allow a firm balance point, it's a part of rehab for all sorts of things. And after using them, one's balance improves. Here's a review of them: https://activesilvers.com/best-foam-balance-pads-for-stability-training/

There's lots of other ways to train, of course. And the choice, as always, is up to you.