To be frank, I think S3 developments like this might happen due to S3 compatibility both on the "server" (Backblaze B2, Minio, SeaweedFS, etc.) and so on as well as on the client side happens, so Amazon is probably not too happy about competition. It's probably a good idea to stay away even from open source by Amazon, given that there is very well, used in production by big companies, working and more independent alternatives.