AFAIK its a CDN issue at AWS. They way the caching works is, that a lot of traffic passes through AWS's edge nodes and that's why so many products (Signal being one if many) are affected.

Besides Whitenoise we need decentralised alternatives to CDNs, something like nsite and self replicating blossom servers might be a way to go. I imagine a nostr based control layer to manage content replication.