Yes, that is because there is no way to bind-mount a folder from the host to a VM. That only works with LXCs. So there are only 4 options:
1.) If you got a spare USB controller you can use PCI passthrough to passthrough the USB controller to your VM. In that case everything that you plug into these USB ports will be available to that VM. But really only that single VM. No other VM nor the host will be able to use all the USB ports of that USB controller. But that would be the most "physical" way to bring your USB HDD into the VM.
2.) You use USB passthrough to pseudo passthrough the USB into the VM. In that case only that VM will be able to use the USB HDD and no other VM nor the host will be able to use it. This isn't recommended because USB passthrough isn't fast and will often cause problems because thr USB needs to be emulated.
3.) You use "
qm set" to pseudo passthrough the USB HDD into your VM. Should be faster and more reliable than option 2 but it is still no real passthrough and emulation/virtualization is involved and the VM will only see that USB HDD as a virtual disk so no SMART and so on are working. And same as option 1 and 2 only this single VM will be able to use that HDD. "Virtio SCSI" should and "SCSI" should be used for best performance and discard capability.
4.) You configure your PVE host or a LXC to work as some kind of NAS running a NFS or SMB server. Then you can add these NFS/SMB shares to your VMs to access the folders on that USB HDD. This is the only way how multiple VMs or the host could share the disk.
I would recommend option 4 using a OpenMediaVault LXC as your NAS where you bind-mount that USB HDD into.