I’ve never had a metal caddy that didn’t rust. It may not be an option for you, but after my last caddy I swore off buying shower storage all together.
I have shampoo, conditioner and body wash. All of those simply sit on the edge of the bathtub until I need them. If you can reduce the amount of stuff you need to 3 or 4 items, nothing might be a good solution.
Otherwise I would encourage you to take a look at plastic ones or other storage solutions.