Are they withered, or still green? Do you have a photo?

Still green. The third-or-so that are still standing look perfectly healthy and there is new growth at the base.

I think a lot of the taller heliconias grow naturally in sheltered (windless) situations. In gardens they often end up more exposed so more prone to falling over. My tallest are 2 to 2.5 metre rostratas which seem to get by even though they're still fairly exposed to wind. But they do have some small trees/shrubs around them which helps.

With yours, it would be a personal, value decision. The green stems would still be feeding the rhizomes, so they have a lot of value for the plants. For people it's a matter of aesthetics, if it looks "untidy" they get rid of it. I tend to side with the plants, so my approach would be to tie them up and only cut them out when they become useless to the plants.

Hi
i have the same problem particularly with the large flowered verticals most notable is rostata . I planted some among a clumping white bird of paradise which supports them but sure becomes a tangled mess lol. In Costa Rica
they used a wire tunnel and the flowers hung down on the inside. Worked beautifully but requires a rather large tunnel. Only other choice seems to be staking?? gary