Why Azure site recovery may not meet RPO?
Looking at Microsoft’s “About Azure Recovery”, we can see this:

RTO and RPO targetsKeep recovery time objectives (RTO) and recovery point objectives (RPO) within organizational limits. Site Recovery provides continuous replication for Azure VMs and VMware VMs, and replication frequency as low as 30 seconds for Hyper-V. You can reduce RTO further by integrating with Azure Traffic Manager.

Data “inside SQL Server” would be data that has not yet been replicated elsewhere, be it Azure, a replication distributor, or a local mirror. Losing 30 seconds of data for most organizations is a tolerable amount of failure, but any company that requires real-time loading and querying will be chomping at the bit about that 30-second gap between the time the primary instance went down and the replicated secondary in Azure picked up