
An IPv6 block...
...should be a /48. Anything smaller is doing it wrong.
IPv6 address: Prefix 6 bytes (/48), subnet 2 bytes, interface 8 bytes (/64).
French cloud provider OVHcloud has opened up a Bring Your Own IP service, which it said allows customers to reuse existing public IPv4 blocks as failover addresses in the event of an outage. The Bring Your Own IP import service, dubbed BYOIP, allows customers to import, via their OVHcloud Control Panel, any existing ranges of …
This must be the reason for offering such a service.
As somebody that plays in that space, there aren't alot of cloud customers that potentially have their own IPv4 blocks sitting around.
The only reason I could see it is if some cloud customer is really tied to OVH, and they want to get away from the absolute shit reputation that OVH IPv4 address space has that gets blocked quite often elsewhere, enough so they go get some rando IPv4 block off an IP broker.
To be honest, I see quite a bit of mileage in a service that cuts out the blocks of hosting companies.
After all, that's not where your customers are, that's where hacking scripts get executed from and none of them do anything about it if you give them a heads up because (a) it makes them money and (b) doing something would cost effort (money), so until there is a way to make them actually pay for it they will be doing sod all.
So yeah, I'd pay for such a filter.