You are correct, this platform limitation is still in place, we can probably mention it in our documentation as well, so thank for raising this - we will corresponding team and update the user guide.
Veeam Backup for Azure is different product, it's cloud-based appliance developed for protection and disaster recovery of Azure workloads, while you are talking about Veeam Backup & Replication and its feature Direct Restore to Azure that allows restoring any workloads (vSphere VM, Hyper-VM, physical machine, etc.) to Azure in the form of VM.
Since it's the feature of Veeam Backup & Replication, it is covered in the corresponding User Guide.
In Microsoft Azure documentation, meaning whatever platform supports for virtual disk size can be backed up and restored by Veeam Backup for Azure product. But I'm not sure whether this information is relevant here, cause you're clearly using Veeam Backup & Replication and its Direct Restore to Azure feature (platform limitations for which have been discussed already). Thanks!