I wear Siemens CIC hearing aids, and in opposition to some of the views here, I wear them ALL the time whilst riding. The advice not to can only be related to BTE or set and forget’ types that don’t have a remote controller, but mine, like most other modern HAs, can be muted, or in my case put on the ‘noisy’ program which then very effectively filters out all that droning noise. I have my controller mounted on the handle bars in a little bracket I made, and in practice always switch to mute, and mute it does, very effectively.
Now this is all because I have CIC type HAs, and I doubt any kind of BTE type could be feasible at all, let alone effective at blocking wind noise.