One obvious benefit of OVH compared to Hetzner is the S3 storage, the Kubernetes framework and a number of other services provided by OVH, don't think Hetzner would provide those services.
Long time Hetzner user, but I would not trust new system (S3 storage) in this case for things beyond playground and tests until it has at least couple of years in production - Hetzner just made it public in ~ Nov 2024.